2013

Read this manual carefully before operating this vehicle.

Il convient de lire attentivement ce manuel avant la première utilisation du véhicule.

Bitte lesen Sie diese Bedienungsanleitung sorgfältig durch, bevor Sie das Fahrzeug in Betrieb nehmen.

Leggere attentamente questo manuale prima di utilizzare questo veicolo.

Lea atentamente este manual antes de utilizar el vehículo.

OWNER’S SERVICE MANUAL

MANUEL D’ATELIER DU
PROPRIETAIRE
FAHRER- UND
WARTUNGSHANDBUCH
MANUALE DI SERVIZIO DEL
PROPRIETARIO
MANUAL DE SERVICIO
DEL PROPIETARIO

WR250F(D)
1HC-28199-52
Read this manual carefully before operating this vehicle. This manual should stay with this vehicle if it is sold.

Il convient de lire attentivement ce manuel avant la première utilisation du véhicule. Le manuel doit étre remis
avec le véhicule en cas de vente de ce dernier.

Bitte lesen Sie diese Bedienungsanleitung sorgfältig durch, bevor Sie das Fahrzeug in Betrieb nehmen. Diese
Bedienungsanleitung muss, wenn das Fahrzeug verkauft wird, beim Fahrzeug verbleiben.

Leggere attentamente questo manuale prima di utilizzare il veicolo. Questo manuale dovrebbe accompa-
gnare il veicolo se viene venduto.

Lea atentamente este manual antes de utilizar el vehículo. Este manual debe acompañar al vehículo si este
se vende.
 2013
Read this manual carefully before operating this vehicle.

OWNER’S SERVICE MANUAL

WR250F(D)
1HC-28199-52-E0
 WR250F (D)
OWNER'S SERVICE MANUAL
©2012 by Yamaha Motor Co., Ltd.
1st Edition, April 2012
All rights reserved. Any reprinting or
unauthorized use without the written
permission of Yamaha Motor Co., Ltd.
is expressly prohibited.
Printed in Japan
FOREWORD IMPORTANT MANUAL • ALWAYS WEAR PROTECTIVE
INFORMATION APPAREL.
INTRODUCTION Particularly important information is When operating this machine, al-
Congratulations on your purchase of distinguished in this manual by the ways wear an approved helmet with
a Yamaha WR series. This model is following notations. goggles or a face shield. Also wear
the culmination of Yamaha's vast ex- heavy boots, gloves, and protective
perience in the production of paceset- clothing. Always wear proper fitting
ting racing machines. It represents This is the safety alert symbol. It is clothing that will not be caught in
the highest grade of craftsmanship used to alert you to potential per- any of the moving parts or controls
and reliability that have made Yama- sonal injury hazards. Obey all safe- of the machine.
ha a leader. ty messages that follow this • ALWAYS MAINTAIN YOUR MA-
This manual explains operation, in- symbol to avoid possible injury or CHINE IN PROPER WORKING
spection, basic maintenance and tun- death. ORDER.
ing of your machine. If you have any For safety and reliability, the ma-
questions about this manual or your chine must be properly maintained.
machine, please contact your Yama- A WARNING indicates a hazardous Always perform the pre-operation
ha dealer. situation which, if not avoided, checks indicated in this manual.
could result in death or serious in- Correcting a mechanical problem
For Canada jury. before you ride may prevent an ac-
The design and manufacture of this cident.
Yamaha machine fully comply with • GASOLINE IS HIGHLY FLAMMA-
the emissions standards for clean air A NOTICE indicates special pre- BLE.
applicable at the date of manufacture. cautions that must be taken to Always turn off the engine while re-
Yamaha has met these standards avoid damage to the vehicle or oth- fueling. Take care to not spill any
without reducing the performance or er property. gasoline on the engine or exhaust
economy of operation of the machine. system. Never refuel in the vicinity
To maintain these high standards, it of an open flame, or while smoking.
is important that you and your Yama- A TIP provides key information to • GASOLINE CAN CAUSE INJURY.
ha dealer pay close attention to the make procedures easier or clearer. If you should swallow some gaso-
recommended maintenance sched- SAFETY INFORMATION line, inhale excess gasoline vapors,
ules and operating instructions con- or allow any gasoline to get into
For Canada
tained within this manual. your eyes, contact a doctor immedi-
This machine is designed for off-road
use only. It is illegal for this machine ately. If any gasoline spills onto
Yamaha continually seeks advance- to be operated on any public street, your skin or clothing, immediately
ments in product design and quality. road, or highway. Off-road use on wash skin areas with soap and wa-
Therefore, while this manual contains public lands may be illegal. Please ter, and change your clothes.
the most current product information check local regulations before riding. • ONLY OPERATE THE MACHINE
available at the time of printing, there IN AN AREA WITH ADEQUATE
may be minor discrepancies between Except for Canada VENTILATION.
your machine and this manual. If you THIS MACHINE IS DESIGNED Never start the engine or let it run
have any questions concerning this STRICTLY FOR COMPETITION for any length of time in an enclosed
manual, please consult your Yamaha USE, ONLY ON A CLOSED area. Exhaust fumes are poison-
dealer. COURSE. It is illegal for this machine ous. These fumes contain carbon
to be operated on any public street, monoxide, which by itself is odor-
road, or highway. Off-road use on less and colorless. Carbon monox-
PLEASE READ THIS MANUAL public lands may also be illegal. ide is a dangerous gas which can
CAREFULLY AND COMPLETELY Please check local regulations before cause unconsciousness or can be
BEFORE OPERATING THIS MA- riding. lethal.
CHINE. DO NOT ATTEMPT TO OP- • THIS MACHINE IS TO BE OPER- • PARK THE MACHINE CAREFUL-
ERATE THIS MACHINE UNTIL YOU ATED BY AN EXPERIENCED RID- LY; TURN OFF THE ENGINE.
HAVE ATTAINED A SATISFACTO- ER ONLY. Always turn off the engine if you are
RY KNOWLEDGE OF ITS CON- Do not attempt to operate this ma- going to leave the machine. Do not
TROLS AND OPERATING chine at maximum power until you park the machine on a slope or soft
FEATURES AND UNTIL YOU HAVE are totally familiar with its character- ground as it may fall over.
BEEN TRAINED IN SAFE AND istics. • THE ENGINE, EXHAUST PIPE,
PROPER RIDING TECHNIQUES. • THIS MACHINE IS DESIGNED TO MUFFLER, AND OIL TANK WILL
REGULAR INSPECTIONS AND BE VERY HOT AFTER THE EN-
BE RIDDEN BY THE OPERATOR
CAREFUL MAINTENANCE, GINE HAS BEEN RUN.
ONLY.
ALONG WITH GOOD RIDING Be careful not to touch them or to
Do not carry passengers on this
SKILLS, WILL ENSURE THAT YOU
machine. allow any clothing item to contact
SAFETY ENJOY THE CAPABILI-
them during inspection or repair.
TIES AND THE RELIABILITY OF
THIS MACHINE.
• PROPERLY SECURE THE MA-
CHINE BEFORE TRANSPORTING
IT.
When transporting the machine in
another vehicle, always be sure it is
properly secured and in an upright
position and that the fuel cock is in
the "OFF" position. Otherwise, fuel
may leak out of the carburetor or
fuel tank.
HOW TO USE THIS MANUAL
FINDING THE REQUIRED PAGE
1. This manual consists of seven
chapters; "General Information",
"Specifications", "Regular inspec-
tion and adjustments", "Tuning",
"Engine", "Chassis" and "Electri-
cal".
2. The table of contents is at the be-
ginning of the manual. Look over
the general layout of the book be-
fore finding then required chapter
and item.
Bend the book at its edge, as
shown, to find the required fore
edge symbol mark and go to a
page for required item and de-
scription.

MANUAL FORMAT
All of the procedures in this manual
are organized in a sequential, step-
by-step format. The information has
been complied to provide the me-
chanic with an easy to read, handy
reference that contains comprehen-
sive explanations of all disassembly,
repair, assembly, and inspection op-
erations.
In this revised format, the condition of
a faulty component will precede an
arrow symbol and the course of ac-
tion required will follow the symbol,
e.g.,
• Bearings
Pitting/damage → Replace.
 2. Numbers "2" are given in the or- 4. A job instruction chart "4" accom-
HOW TO READ DESCRIPTIONS
der of the jobs in the exploded di- panies the exploded diagram,
To help identify parts and clarify pro-
agram. A number that is enclosed providing the order of jobs, names
cedure steps, there are exploded dia-
by a circle indicates a disassem- of parts, notes in jobs, etc.
grams at the start of each removal
bly step. 5. For jobs requiring more informa-
and disassembly section.
3. An explanation of jobs and notes tion, the step-by-step format sup-
1. An easy-to-see exploded diagram
is presented in an easy-to-read plements "5" are given in addition
"1" is provided for removal and
way by the use of symbol marks to the exploded diagram and job
disassembly jobs.
"3". The meanings of the symbol instruction chart.
marks are given on the next page.

3 5

ILLUSTRATED SYMBOLS (Refer to Illustrated symbols "1" to "7" are used Illustrated symbols "14" to "15" in the
the illustration) to identify the specifications appear- exploded diagrams indicate where to
ing in the text. apply a locking agent and where to in-
1. With engine mounted stall new parts.
2. Filling fluid 14. Apply locking agent (LOC-
3. Lubricant TITE®)
4. Special tool 15. Use new one
5. Tightening
6. Specified value, Service limit
7. Resistance (Ω), Voltage (V),
Electric current (A)
Illustrated symbols "8" to "13" in the
exploded diagrams indicate grade of
lubricant and location of lubrication
point.
8. Apply engine oil
9. Apply molybdenum disulfide oil
10. Apply brake fluid
11. Apply lightweight lithium-soap
base grease
12. Apply molybdenum disulfide
grease
13. Apply silicone grease
TABLE OF CONTENTS
GENERAL INFORMATION 1
SPECIFICATIONS 2
REGULAR INSPECTION AND
ADJUSTMENTS 3
TUNING 4
ENGINE 5
CHASSIS 6
ELECTRICAL 7
 CONTENTS

CHAPTER 1 CHAPTER 3 OIL FILTER ELEMENT

AND WATER PUMP .......5-34
GENERAL INFOR- REGULAR INSPEC- BALANCER ....................5-39
MATION TION AND AD- OIL PUMP .......................5-41
KICK SHAFT AND SHIFT
JUSTMENTS SHAFT ............................5-44
LOCATION OF AC MAGNETO AND
IMPORTANT LABELS ..... 1-1 STARTER CLUTCH........5-49
PERIODIC MAINTENANCE
DESCRIPTION ................. 1-5 ENGINE REMOVAL........5-54
CHART FOR THE EMISSION
CONSUMER CRANKCASE AND
CONTROL SYSTEM (For
INFORMATION................. 1-6 CRANKSHAFT ...............5-58
Canada) ............................ 3-1
INCLUDED PARTS .......... 1-6 TRANSMISSION,
GENERAL MAINTENANCE
IMPORTANT SHIFT CAM AND
AND LUBRICATION CHART
INFORMATION................. 1-6 SHIFT FORK...................5-64
(For Canada) .................... 3-2
CHECKING OF
MAINTENANCE INTER-
CONNECTION.................. 1-7
VALS FOR COMPETITION CHAPTER 6
SPECIAL TOOLS ............. 1-8
USE................................... 3-3
CONTROL FUNCTIONS .. 1-12
PRE-OPERATION CHASSIS
MULTI-FUNCTION
INSPECTION AND
DISPLAY ........................ 1-13
MAINTENANCE................ 3-7
STARTING AND FRONT WHEEL AND
ENGINE ............................ 3-8
BREAK-IN ...................... 1-18 REAR WHEEL ..................6-1
CHASSIS ........................ 3-19
TORQUE-CHECK FRONT BRAKE AND
ELECTRICAL ................. 3-29
POINTS........................... 1-20 REAR BRAKE ..................6-6
CLEANING AND FRONT FORK.................6-16
STORAGE ...................... 1-21 CHAPTER 4 HANDLEBAR..................6-23
STEERING ......................6-27
TUNING SWINGARM ....................6-31
CHAPTER 2 REAR SHOCK
SPECIFICATIONS ENGINE ABSORBER....................6-36
(Except for Canada) ........ 4-1
CHASSIS .......................... 4-5 CHAPTER 7
GENERAL
SPECIFICATIONS............ 2-1 ELECTRICAL
MAINTENANCE CHAPTER 5
SPECIFICATIONS............ 2-3
TIGHTENING ENGINE ELECTRICAL COMPO-
TORQUES ...................... 2-12 NENTS AND WIRING
LUBRICATION RADIATOR ....................... 5-1 DIAGRAM .........................7-1
DIAGRAMS .................... 2-19 CARBURETOR................. 5-4 IGNITION SYSTEM...........7-3
CABLE ROUTING AIR INDICTOIN ELECTRIC STARTING
DIAGRAM....................... 2-21 SYSTEM ......................... 5-12 SYSTEM............................7-5
CAMSHAFTS.................. 5-14 CHARGING SYSTEM .....7-13
CYLINDER HEAD........... 5-19 THROTTLE POSITION
VALVES AND VALVE SENSOR SYSTEM .........7-15
SPRINGS ........................ 5-21 LIGHTING SYSTEM .......7-18
CYLINDER AND SIGNALING SYSTEM.....7-20
PISTON........................... 5-25
CLUTCH ......................... 5-29
 LOCATION OF IMPORTANT LABELS

GENERAL INFORMATION
LOCATION OF IMPORTANT LABELS
Please read the following important labels carefully before operating this vehicle.

CANADA

Essence super sans

plomb seulement.
3FB-2415E-12

1-1
 LOCATION OF IMPORTANT LABELS

EUROPE

1-2
 LOCATION OF IMPORTANT LABELS

AUS, NZ, ZA

1-3
 LOCATION OF IMPORTANT LABELS

Familiarize yourself with the following pictograms and read the explanatory text.
Read Owner's service manual.

This unit contains high-pressure nitrogen gas. Mishandling can cause explosion. Do not incinerate,
puncture or open.

Turn off the main switch after riding to avoid draining the battery.

Use unleaded gasoline only.

Measure tire pressure when tires are cold.

Adjust tire pressure.

Improper tire pressure can cause loss of control.
Loss of control can result in severe injury or death.

1-4
 DESCRIPTION

DESCRIPTION

1. Clutch lever 14. Headlight

2. Hot starter lever 15. Radiator
3. Engine stop switch 16. Coolant drain bolt
4. Multi-function display 17. Rear brake pedal
5. Main switch 18. Valve joint
6. Start switch 19. Fuel cock
7. Front brake lever 20. Cold starter knob
8. Throttle grip 21. Air cleaner
9. Radiator cap 22. Catch tank
10. Fuel tank cap 23. Drive chain
11. Taillight 24. Oil level check window
12. Kickstarter crank 25. Shift pedal
13. Fuel tank 26. Front fork

• The machine you have purchased may differ slightly from those shown in the following.
• Designs and specifications are subject to change without notice.

1-5
 CONSUMER INFORMATION

CONSUMER INFORMATION DRIVE CHAIN SPROCKET GUIDE

There are two significant reasons for (For EUROPE)
knowing the serial number of your Use the drive chain sprocket guide
machine: "1" when installing the included drive
1. When ordering parts, you can sprockt (13T).
give the number to your Yamaha
dealer for positive identification of
the model you own.
2. If your machine is stolen, the au- A. Left
thorities will need the number to B. Right
search for and identify your ma- INCLUDED PARTS
chine. VALVE JOINT
VEHICLE IDENTIFICATION This valve joint "1" prevents fuel from
NUMBER flowing out and is installed to the fuel IMPORTANT INFORMATION
The vehicle identification number "1" tank breather hose. PREPARATION FOR REMOVAL
is stamped on the right of the steering AND DISASSEMBLY
head pipe. 1. Remove all dirt, mud, dust, and
In this installation, make sure the foreign material before removal
arrow faces the fuel tank and also and disassembly.
downward. • When washing the machine with
high pressured water, cover the
parts follows.
Silencer exhaust port
Side cover air intake port
Water pump housing hole at the
ENGINE SERIAL NUMBER bottom
The engine serial number "1" is Drain hole on the cylinder head
stamped into the elevated part of the (right side)
right-side of the engine. SPARK PLUG WRENCH All electrical components
This spark plug wrench "1" is used to
remove and install the spark plug.

MODEL LABEL
The model label "1" is affixed to the
frame under the rider's seat. This in- NIPPLE WRENCH
formation will be needed to order This nipple wrench "1" is used to
spare parts. tighten the spoke.

2. Use proper tools and cleaning

equipment. Refer to "SPECIAL
TOOLS" section.

VEHICLE EMISSION CONTROL JET NEEDLE PULL-UP TOOL

INFORMATION LABEL (For (Except for Canada)
Canada) The jet needle pull-up tool "1" is used
The Vehicle Emission Control Infor- to pull the jet needle out of the carbu-
mation label "1" is affixed at the loca- retor.
tion in the illustration. This label
shows specifications related to ex-
haust emissions as required by feder-
al law, state law and Environment
Canada.

1-6
 CHECKING OF CONNECTION

3. When disassembling the ma- BEARINGS AND OIL SEALS

chine, keep mated parts together. 1. Install the bearing(s) "1" and oil
They include gears, cylinders, seal(s) "2" with their manufactur-
pistons, and other mated parts er's marks or numbers facing out-
that have been "mated" through ward. (In other words, the
normal wear. Mated parts must stamped letters must be on the
be reused as an assembly or re- side exposed to view.) When in-
placed. stalling oil seal(s), apply a light
coating of lightweight lithium base 3. Connect and disconnect the con-
grease to the seal lip(s). Oil the nector two or three times.
bearings liberally when installing. 4. Pull the lead to check that it will
not come off.
5. If the terminal comes off, bend up
Do not use compressed air to spin the pin "1" and reinsert the termi-
the bearings dry. This causes dam- nal into the connector.
age to the bearing surfaces.
4. During the machine disassembly,
clean all parts and place them in
trays in the order of disassembly.
This will speed up assembly time
and help assure that all parts are
correctly reinstalled.

6. Connect:
• Connector

The two connectors "click" together.

7. Check for continuity with a tester.

5. Keep away from fire. • If there in no continuity, clean the

ALL REPLACEMENT PARTS terminals.
1. We recommend to use Yamaha CIRCLIPS • Be sure to perform the steps 1 to 7
genuine parts for all replace- 1. All circlips should be inspected listed above when checking the
ments. Use oil and/or grease rec- carefully before reassembly. Al- wire harness.
ommended by Yamaha for ways replace piston pin clips after • For a field remedy, use a contact re-
assembly and adjustment. one use. Replace distorted cir- vitalizer available on the market.
GASKETS, OIL SEALS AND O- clips. When installing a circlip "1", • Use the tester on the connector as
RINGS make sure that the sharp-edged shown.
1. All gaskets, oil seals, and O-rings corner "2" is positioned opposite
should be replaced when an en- to the thrust "3" it receives. See
gine is overhauled. All gasket sur- the sectional view.
faces, oil seal lips, and O-rings
must be cleaned.
2. Properly oil all mating parts and
bearings during reassembly. Ap-
ply grease to the oil seal lips.
LOCK WASHERS/PLATES AND
COTTER PINS
1. All lock washers/plates "1" and
cotter pins must be replaced CHECKING OF
when they are removed. Lock CONNECTION
tab(s) should be bent along the Dealing with stains, rust, moisture,
bolt or nut flat(s) after the bolt or etc. on the connector.
nut has been properly tightened. 1. Disconnect:
• Connector
2. Dry each terminal with an air
blower.

1-7
 SPECIAL TOOLS

SPECIAL TOOLS
The proper special tools are necessary for complete and accurate tune-up and assembly. Using the correct special tool will
help prevent damage caused by the use of improper tools or improvised techniques. The shape and part number used for
the special tool differ by country, so two types are provided. Refer to the list provided to avoid errors when placing an order.

• For U.S.A. and Canada, use part number starting with "YM-", "YU-" or "ACC-".
• For others, use part number starting with "90890-".

Tool name/Part number How to use Illustration

Crankcase separating tool These tool is used to remove the
YU-1135-A, 90890-01135 crankshaft from either case.

Dial gauge and stand These tools are used to check each
YU-3097, 90890-01252 part for runout or bent.
Stand
YU-1256

Crankshaft installing tool These tools are used to install the

Crankshaft installing pot crankshaft.
YU-90050, 90890-01274
Crankshaft installing bolt
YU-90050, 90890-01275
Spacer (crankshaft installer)
YU-91044, 90890-04081
Adapter (M12)
YU-90063, 90890-01278

Piston pin puller set This tool is used to remove the pis-
YU-1304, 90890-01304 ton pin.

Radiator cap tester These tools are used for checking

YU-24460-01, 90890-01325 the cooling system.
Radiator cap tester adapter
YU-33984, 90890-01352

1-8
 SPECIAL TOOLS

Tool name/Part number How to use Illustration

Steering nut wrench This tool is used when tighten the
YU-33975, 90890-01403 steering ring nut to specification.

Damper rod holder Use this tool to remove and install

YM-01494, 90890-01494 the damper rod.

Fork seal driver This tool is used when install the fork
YM-A0948, 90890-01502 oil seal.

Spoke nipple wrench This tool is used to tighten the

YM-01521, 90890-01521 spoke.

Sheave holder This tool is used for when loosening

YS-1880-A, 90890-01701 or tightening the flywheel magneto
securing nut.

Pocket tester Use this tool to inspect the coil resis-

YU-3112-C, 90890-03112 tance, output voltage and amper-
age.

1-9
 SPECIAL TOOLS

Tool name/Part number How to use Illustration

Timing light This tool is necessary for checking
YM-33277-A, 90890-03141 ignition timing.

Valve spring compressor This tool is needed to remove and

YM-4019, 90890-04019 install the valve assemblies.

Clutch holding tool This tool is used to hold the clutch

YM-91042, 90890-04086 when removing or installing the
clutch boss securing nut.

Valve guide remover This tool is needed to remove and

Intake 4.0 mm (0.16 in) install the valve guide.
Exhaust 4.5 mm (0.18 in)
YM-4111, 90890-04111
YM-4116, 90890-04116

Valve guide installer This tool is needed to install the

Intake 4.0 mm (0.16 in) valve guide.
Exhaust 4.5 mm (0.18 in)
YM-4112, 90890-04112
YM-4117, 90890-04117

Valve guide reamer This tool is needed to rebore the

Intake 4.0 mm (0.16 in) new valve guide.
Exhaust 4.5 mm (0.18 in)
YM-4113, 90890-04113
YM-4118, 90890-04118

1-10
 SPECIAL TOOLS

Tool name/Part number How to use Illustration

Valve spring compressor adapter This tool is needed to remove and
19.5 mm install the valve assemblies.
YM-04114
Valve spring compressor attach-
ment
90890-04114

Rotor puller This tool is used to remove the fly-

YM-04141, 90890-04141 wheel magneto.

Dynamic spark tester This instrument is necessary for

YM-34487 checking the ignition system compo-
Ignition checker nents.
90890-06754

Vacuum/pressure pump gauge set This tool is used to check the air in-
YB-35956-A, 90890-06756 duction system.

YAMAHA Bond No. 1215 (Three- This sealant (Bond) is used for
Bond® No. 1215) crankcase mating surface, etc.
90890-85505

1-11
 CONTROL FUNCTIONS

CONTROL FUNCTIONS CLUTCH LEVER

MAIN SWITCH The clutch lever "1" is located on the
Functions of the respective switch po- left handlebar; it disengages or en-
sitions are as follows: gages the clutch. Pull the clutch lever
ON: to the handlebar to disengage the
The engine can be started only at this clutch, and release the lever to en-
position. gage the clutch. The lever should be
OFF: pulled rapidly and released slowly for
All electrical circuits are switched off. smooth starts. FRONT BRAKE LEVER
Main switch indicator light The front brake lever "1" is located on
The main switch "1" is equipped with the right handlebar. Pull it toward the
an indicator light "2" to avoid forget- handlebar to activate the front brake.
ting to turn it off. This light functions
as follows.
• It lights up with the main switch
"ON".
• It goes out when the engine in-
creases its speed after being start- SHIFT PEDAL
ed. The gear ratios of the constant-mesh
• It lights up again when the engine is 5 speed transmission are ideally
stopped. spaced. The gears can be shifted by REAR BRAKE PEDAL
using the shift pedal "1" on the left The rear brake pedal "1" is located on
side of the engine. the right side of the machine. Press
If the indicator light will not light up
down on the brake pedal to activate
with the main switch "ON", it shows a
the rear brake.
lack of the battery voltage. Recharge
the battery.

KICKSTARTER CRANK
Rotate the kickstarter crank "1" away
from the engine. Push the starter FUEL COCK
down lightly with your foot until the The fuel cock supplies fuel from the
ENGINE STOP SWITCH gears engage, then kick smoothly tank to carburetor and also filters the
The engine stop switch "1" is located and forcefully to start the engine. This fuel. The fuel cock has the three posi-
on the left handlebar. Continue push- model has a primary kickstarter crank tions:
ing the engine stop switch till the en- so the engine can be started in any OFF:
gear if the clutch is disengaged. In With the lever in this position, fuel will
gine comes to a stop.
normal practices, however, shift to not flow. Always return the lever to
neutral before starting. this position when the engine is not
running.
ON:
With the lever in this position, fuel
flows to the carburetor. Normal riding
is done with the lever in this position.
RES:
With the lever in this position fuel
START SWITCH flows to the carburetor from the re-
The start switch "1" is located on the serve section of the fuel tank after the
right handlebar. Push this switch to THROTTLE GRIP main supply of the fuel has been de-
crank the engine with the starter. The throttle grip "1" is located on the pleted. Normal riding is possible with
right handlebar; it accelerates or de- the lever is in this position, but it is
celerates the engine. For accelera- recommended to add fuel as soon as
tion, turn the grip toward you; for possible.
deceleration, turn it away from you.

1-12
 MULTI-FUNCTION DISPLAY

COLD STARTER KNOB MULTI-FUNCTION DISPLAY BASIC MODE

When cold, the engine requires a Changing speedometer display
richer air-fuel mixture for starting. A (for U.K.)
separate starter circuit, which is con- Be sure to stop the machine before 1. Push the "SLCT2" button for 2
trolled by the cold starter knob "1", making any setting changes to the seconds or more to change the
supplies this mixture. Pull the cold multi-function display. speedometer units. The speed-
starter knob out to open the circuit for ometer display will change in the
The multi-function display is
starting. When the engine has following order:
equipped with the following:
warmed up, push it in to close the cir- MPH → km/h → MPH.
BASIC MODE:
cuit.
• Speedometer
• Clock
• Two tripmeters (which shows the
distance that has been traveled
since it was last set to zero)
RACE MODE:
• Timer (which shows the time that
has been accumulated since the
start of timer measurement) Setting the time
HOT STARTER LEVER
• Tripmeter (which shows the accu- 1. Push the "SLCT1" button for 2
The hot starter lever "1" is used when
mulated travel distance in timer seconds or more to enter the time
starting a warm engine. Use the hot
measurement) setting mode.
starter lever when starting the engine
• Change tripmeter digits (capable of 2. Push the "RST" button to change
again immediately after it was
change to any given ones) the display for time indication.
stopped (the engine is still warm).
DESCRIPTION The display will change in the fol-
Pulling the hot starter lever injects
Operation buttons: lowing order:
secondary air to thin the air-fuel mix-
1. Select button "SLCT 1" Hour → Minute → Second → Hour.
ture temporarily, allowing the engine
to be started more easily. 2. Select button "SLCT 2"
3. Reset button "RST" The digits capable of setting go on
Screen display: flashing.
4. Tripmeter indicator
5. Tripmeter indicator
6. Timer indicator
7. Clock/Timer
8. Speedometer
9. Odometer/Tripmeter
SIDESTAND
This sidestand "1" is used to support The operation buttons can be pushed
only the machine when standing or in the following two manners:
transporting it. Short push: Push the button. ( )
Long push: Push the button for 2 sec- 3. Push the "SLCT1" button (plus) or
onds or more. ( ) "SLCT2" button (minus) and
• Never apply additional force to change the time. A long push on
the sidestand. the button will fast-forward the
• Hold up the sidestand before time.
starting out.

4. To end the setting, push the

"RST" button for 2 seconds or
more.

• In a 30-second absence of button

operation, the setting will come to
an end with the indicated time.
• To reset the seconds, push the
"SLCT1" button or "SLCT2" button.

1-13
 MULTI-FUNCTION DISPLAY

Changing odometer and tripmeter Manual start

A/B (TRIP A/B)
1. Push the "SLCT2" button to Initial setting at changeover to RACE
change the tripmeter display. The MODE will remain for manual start.
display will change in the follow-
ing order: 1. Check that changeover to RACE
Odometer → TRIP A → TRIP B → MODE has been made. (Refer to
TRIP A → Odometer. "Changeover from BASIC MODE
to RACE MODE".)

When the machine is made ready for

Returning to BASIC MODE from a run by manual start, and will
RACE MODE start flashing.

It is possible to return to BASIC 2. Start timer measurement by

MODE with timer measurement at a pushing the "RST" button.
stop.

1. Check that the timer is not in op-

eration. If the timer is in operation,
To reset the digits, select the tripme- stop the timer by pushing the
ter involved and push the "RST" but- "SLCT1" button and "SLCT2" but-
3. When stopping timer measure-
ton for 2 seconds or more. ton at the same time.
ment, pushing the "SLCT1" but-
ton and "SLCT2" button at the
same time.

If the machine is run while timer mea-

surement is not made, no change will
occur to the digit in tripmeter A (TRIP
A).
2. Push the "SLCT1" button and
CHANGEOVER TO BASIC MODE/ "SLCT2" button for 2 seconds or
RACE MODE more at the same time to change
over to BASIC MODE.
• Measurement using the timer func-
tion can be made in RACE MODE.
• Indicator will light up as an
identifier that shows RACE MODE
has been selected. 4. To resume the measurement,
• RACE MODE cannot display the again push the "SLCT1" button
functions as in BASIC MODE. and "SLCT2" button at the same
• Changeover to RACE MODE forc- time.
es the digits for tripmeter A (TRIP Auto start
A) in BASIC MODE to be reset. 1. Check that changeover has been
made to RACE MODE. (Refer to
Changeover from BASIC MODE to RACE MODE
"Changeover from BASIC MODE
RACE MODE Putting measurement on standby
to RACE MODE".)
1. Push the "SLCT1" button and
2. Make the machine ready for a run
"SLCT2" button for 2 seconds or Starting measurement consists of the by pushing the "SLCT1" button for
more at the same time to change following two starts, either of which 2 seconds or more.
over to RACE MODE. can be selected.
• Manual start
Starting measurement by the rider When the measurement is made
Changeover to RACE MODE will put
himself operating the button. (A long ready for a run by auto start, and
manual start measurement on stand-
push on the "SLCT2" button will put will start flashing. Timer display
by causing and to flash. (For
measurement on standby.) will turn on scrolling from left to right.
manual start, refer to "Putting mea-
surement on standby" in "RACE • Auto start
MODE".) Starting timer measurement automat-
ically on detection of the movement of
the machine. (A long push on the
"SLCT1" button will put measurement
on standby.)

1-14
 MULTI-FUNCTION DISPLAY

Resetting tripmeter A (TRIP A) and

timer
3. Run the machine and start timer
1. Check that the timer is not in op-
measurement.
eration. If the timer is in operation,
4. To stop timer measurement,
stop it by pushing the "SLCT1"
pushing the "SLCT1" button and
button and "SLCT2" button at the
"SLCT2" button at the same time.
same time.
2. Reset all measured data by push-
If the machine is run while timer mea- ing the "RST" button for 2 sec-
surement is not made, no change will onds or more.
occur to the digit in tripmeter A (TRIP
A).
• Resetting will reset the timer display
and travel distance display and put
measurement on standby.
• Auto start attempt will put measure-
ment on standby as such. Likewise,
manual start attempt will put mea-
surement on standby as such.

5. To resume the measurement,

again pushing the "SLCT1" button
and "SLCT2" button at the same
time.
Resetting measurement data

Resetting can be made in the follow- Correcting tripmeter A (TRIP A)

ing two manners. 1. Change the travel distance dis-
Resetting is possible while timer play by pushing the "SLCT1" but-
measurement is made: ton (plus) or "SLCT2" button
• Reset tripmeter A. (minus). A long push on the but-
Resetting is possible while timer ton will fast-forward the change.
measurement is not made:
• Reset tripmeter A and timer.
Change can be made any time while
Resetting tripmeter A (TRIP A) timer measurement is or is not being
1. Check that the timer is in opera- made.
tion. If the timer is not in opera-
tion, start the timer by pushing the
"SLCT1" button and "SLCT2" but-
ton at the same time.
2. Reset tripmeter A (TRIP A) dis-
play by pushing the "RST" button
for 2 seconds or more.

If reset, and travel distance dis-

play will go on flashing for four sec-
onds.

1-15
 MULTI-FUNCTION DISPLAY

FUNCTION DIAGRAM

A short push on the button changes

the operation in the arrowed direction.
Meter function
A short push on the button changes
the operation in both arrowed directions.
Function that can be performed whether
A long push on the button changes the the time is or is not in operation.
operation in the arrowed direction.
A long push on the button changes the Extent to which the meter can operate
operation in both arrowed directions.

Clock

BASIC MODE

Tripmeter Speedometer
(for U.K.)
ODO TRIP A TRIP B
ODO MPH km/h MPH

Putting measurement on
standby

Auto start
Manual start

Measurement starts as the

machine moves
RACE MODE
Timer not in
Timer in operation operation

Reset Correct
TRIP A TRIP A Correct Reset
TRIP A TRIP A &
timer

1-16
 MULTI-FUNCTION DISPLAY

The following diagram illustrates the

multi-function display regarding the
direction and operation condition in-
volved in each of its functions.

A. A short push on the button

changes the operation in the ar-
rowed direction.
B. A short push on the button
changes the operation in both
arrowed directions.
C. A long push on the button
changes the operation in the ar-
rowed direction.
D. A long push on the button
changes the operation in both
arrowed directions.
E. Meter function
F. Function that can be performed
whether the time is or is not in
operation.
G. Extent to which the meter can
operate
1. BASIC MODE
2. Clock
3. Trip meter
4. Speedometer (for U.K.)
5. RACE MODE
6. Putting measurement on stand-
by
7. Manual start
8. Auto start
9. Measurement starts as the ma-
chine moves
10. Timer in operation
11. Reset TRIP A
12. Correct TRIP A
13. Timer not in operation
14. Reset TRIP A & timer

1-17
 STARTING AND BREAK-IN

STARTING AND BREAK-IN

If the engine fails to start by pushing
FUEL • The carburetor on this machine
the start switch, release the switch,
Always use the recommended fuel as has a built-in accelerator pump.
wait a few seconds, and then try
stated below. Also, be sure to use Therefore, when starting the en-
again. Each starting attempt should
new gasoline. gine, do not operate the throttle
be as short as possible to preserve
Recommended fuel: or the spark plug will foul.
the battery. Do not crank the engine
Premium unleaded • Unlike a two-stroke engine, this
more than 10 seconds on any one at-
gasoline only with a re- engine cannot be kick started
tempt. If the engine does not start
search octane number when the throttle is open be-
with the starter motor, try using the
of 95 or higher. cause the kickstarter may kick
kickstarter crank.
back. Also, if the throttle is open
the air/fuel mixture may be too
lean for the engine to start.
Use only unleaded gasoline. The • If the starter motor will not turn
• Before starting the machine, per-
use of leaded gasoline will cause when pushing the start switch,
form the checks in the pre-opera-
severe damage to the engine inter- stop pushing it immediately and
tion check list.
nal parts such as valves, piston kick start the engine in order to
rings, and exhaust system, etc. AIR FILTER MAINTENANCE avoid the load on the motor.
According to "CLEANING THE AIR • Do not open the throttle while
FILTER ELEMENT" section in the kicking the kickstarter crank.
If knocking or pinging occurs, use a
CHAPTER 3, apply the foam-air-filter Otherwise, the kickstarter crank
different brand of gasoline or higher
oil or its equivalent to the element. may kick back.
octane grade.
(Excess oil in the element may ad-
versely affect engine starting.) 7. Return the cold starter knob to its
original position and run the en-
STARTING A COLD ENGINE
• For refueling, be sure to stop the gine at 3,000–5,000 r/min for 1 or
engine and use enough care not 2 minutes.
This model is equipped with an igni-
to spill any fuel. Also be sure to
tion circuit cut-off system. The engine
avoid refueling close to a fire. Since this model is equipped with an
can be started under the following
• Refuel after the engine, exhaust accelerator pump, if the engine is
conditions.
pipe, etc. have cooled off. raced (the throttle opened and
• When the transmission is in neutral.
closed), the air/fuel mixture will be too
Gasohol (For Canada) • When the clutch is disengaged with
rich and the engine may stall. Also
There are two types of gasohol: gas- the transmission in any position.
unlike a two-stroke engine, this model
ohol containing ethanol and that con- However, it is recommended to shift
can idle.
taining methanol. Gasohol containing into neutral before starting the en-
ethanol can be used if the ethanol gine.
content does not exceed 10%. Gaso-
1. Inspect the coolant level. Do not warm up the engine for ex-
hol containing methanol is not recom-
2. Turn the fuel cock to "ON". tended periods of time.
mended by Yamaha because it can
3. Push on the main switch to "ON".
cause damage to the fuel system or
4. Shift the transmission into neutral. STARTING A WARM ENGINE
vehicle performance problems.
5. Fully open the cold starter knob Do not operate the cold starter knob
HANDLING NOTE "1". and throttle. Pull the hot starter lever
"1" and start the engine by pushing
Never start or run the engine in a the start switch or by kicking the kick-
closed area. The exhaust fumes starter crank forcefully with a firm
are poisonous; they can cause stroke. As soon as the engine starts,
loss of consciousness and death Release the hot starter lever to close
in a very short time. Always oper- the air passage.
ate the machine in a well-ventilated
area.
6. Start the engine by pushing the
start switch or by kicking the kick-
starter crank.

1-18
 STARTING AND BREAK-IN

Restarting an engine after a fall BREAK-IN PROCEDURES

Pull the hot starter lever and start the 1. Before starting the engine, fill the
engine. As soon as the engine starts, fuel tank with the fuel.
Release the hot starter lever to close 2. Perform the pre-operation checks
the air passage. on the machine.
The engine fails to start 3. Start and warm up the engine.
Pull the hot starter lever all the way Check the idle speed, and check
out and while holding the lever, kick the operation of the controls and
the kickstarter crank 10 to 20 times to the engine stop switch. Then, re-
clear the engine. Then, restart the en- start the engine and check its op-
gine. Refer to "Restarting an engine eration within no more than 5
after a fall". minutes after it is restarted.
Thro 4. Operate the machine in the lower
ttle Cold Hot gears at moderate throttle open-
grip start- start- ings for five to eight minutes.
op- er er le- 5. Check how the engine runs when
era- knob ver the machine is ridden with the
tion* throttle 1/4 to 1/2 open (low to me-
dium speed) for about one hour.
Ope
Air tempera- 6. Restart the engine and check the
n3
ture = less operation of the machine through-
or 4 ON OFF
than 5 °C (41 out its entire operating range. Re-
time
St °F) start the machine and operate it
s
ar for about 10 to 15 more minutes.
ti Air tempera-
n ture = more Non
ON OFF
g than 5 °C (41 e After the break-in or before each
a °F) ride, you must check the entire ma-
c Air tempera- chine for loose fittings and fasten-
ol ture (normal ers as per "TORQUE-CHECK
d temperature) POINTS". Tighten all such fasten-
e = between 5 Non ON/
OFF ers as required.
n °C (41 °F) e OFF
gi and 25 °C
n (77 °F)
e
Air tempera-
ture = more Non
OFF OFF
than 25 °C e
(77 °F)
Starting an en-
Non
gine after a long ON OFF
e
period of time
Restarting a Non
OFF ON
warm engine e
Restarting an en- Non
OFF ON
gine after a fall e
* Operate the throttle grip before kick
starting.

Observe the following break-in

procedures during initial operation
to ensure optimum performance
and avoid engine damage.

1-19
 TORQUE-CHECK POINTS

TORQUE-CHECK POINTS
Frame construction Frame to rear frame
Combined seat and fuel tank Fuel tank to frame
Exhaust system Silencer to rear frame
Engine mounting Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering Steering stem to handlebar Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Suspension Front Steering stem to front fork Front fork to upper bracket
Front fork to lower bracket
Rear For link type Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Installation of rear shock absorber Rear shock absorber to frame
Installation of swingarm Tightening of pivot shaft
Wheel Installation of wheel Front Tightening of wheel axle
Tightening of axle holder
Rear Tightening of wheel axle
Wheel to rear wheel sprocket
Brake Front Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Tightening of brake hose holder
Rear Brake pedal to frame
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Tightening of brake hose holder
Fuel system Fuel tank to fuel cock
Lubrication system Tightening of oil hose clamp

Concerning the tightening torque, refer to "TIGHTENING TORQUES" section in the CHAPTER 2.

1-20
 CLEANING AND STORAGE

CLEANING AND STORAGE STORAGE

CLEANING If your machine is to be stored for 60
Frequent cleaning of your machine days or more, some preventive mea-
will enhance its appearance, maintain sures must be taken to avoid deterio-
good overall performance, and ex- ration. After cleaning the machine
tend the life of many components. thoroughly, prepare it for storage as
1. Before washing the machine, follows:
block off the end of the exhaust 1. Drain the fuel tank, fuel lines, and
pipe to prevent water from enter- the carburetor float bowl.
ing. A plastic bag secured with a 2. Remove the spark plug, pour a ta-
rubber band may be used for this blespoon of SAE 10W-40 motor
purpose. oil in the spark plug hole, and re-
2. If the engine is excessively install the plug. With the engine
greasy, apply some degreaser to stop switch pushed in, kick the en-
it with a paint brush. Do not apply gine over several times to coat the
degreaser to the chain, sprockets, cylinder walls with oil.
or wheel axles. 3. Remove the drive chain, clean it
3. Rinse the dirt and degreaser off thoroughly with solvent, and lubri-
with a garden hose; use only cate it. Reinstall the chain or store
enough pressure to do the job. it in a plastic bag tied to the frame.
4. Lubricate all control cables.
5. Block the frame up to raise the
Do not use high-pressure washers wheels off the ground.
or steam-jet cleaners since they 6. Tie a plastic bag over the exhaust
cause water seepage and deterio- pipe outlet to prevent moisture
ration seals. from entering.
7. If the machine is to be stored in a
4. After the majority of the dirt has humid or salt-air environment,
been hosed off, wash all surfaces coat all exposed metal surfaces
with warm water and a mild deter- with a film of light oil. Do not apply
gent. Use an old toothbrush to oil to rubber parts or the seat cov-
clean hard-to-reach places. er.
5. Rinse the machine off immediate-
ly with clean water, and dry all
Make any necessary repairs before
surfaces with a soft towel or cloth.
the machine is stored.
6. Immediately after washing, re-
move excess water from the
chain with a paper towel and lubri-
cate the chain to prevent rust.
7. Clean the seat with a vinyl uphol-
stery cleaner to keep the cover
pliable and glossy.
8. Automotive wax may be applied
to all painted or chromed surfac-
es. Avoid combination cleaner-
waxes, as they may contain abra-
sives.
9. After completing the above, start
the engine and allow it to idle for
several minutes.

1-21
 GENERAL SPECIFICATIONS

SPECIFICATIONS
GENERAL SPECIFICATIONS
Model name: WR250FD (USA, CDN, AUS, NZ)
WR250F (EUROPE, ZA)
Model code number: 1HC9 (USA)
1HCA (CDN)
1HCB (EUROPE)
1HCC (AUS, NZ, ZA)
Dimensions: USA, CDN, ZA AUS, NZ EUROPE
Overall length 2,165 mm (85.24 2,175 mm (85.63 2,185 mm (86.02
in) in) in)
Overall width 825 mm (32.48 in) ← ←
Overall height 1,300 mm (51.18 1,305 mm (51.38 ←
in) in)
Seat height 980 mm (38.58 in) 990 mm (38.98 in) ←
Wheelbase 1,480 mm (58.27 ← 1,485 mm (58.46
in) in)
Minimum ground clearance 365 mm (14.37 in) ← ←
Weight: EUROPE, AUS,
USA CDN, ZA
NZ
Curb weight 115 kg (254 lb) 116 kg (256 lb) 117 kg (258 lb)
Engine:
Engine type Liquid cooled 4-stroke, DOHC
Cylinder arrangement Single cylinder
Displacement 250 cm3 (8.80 Imp oz, 8.45 US oz)
Bore × stroke 77.0 × 53.6 mm (3.03 × 2.11 in)
Compression ratio 12.5 : 1
Starting system Kick and electric starter
Lubrication system: Dry sump
Oil type or grade:
Engine oil Recommended brand: YAMALUBE
SAE 10W-30, SAE 10W-40, SAE 10W-50,
SAE 15W-40, SAE 20W-40 or SAE 20W-50
API service SG type or higher,
JASO standard MA

Oil capacity:
Engine oil
Periodic oil change 1.1 L (0.97 Imp qt, 1.16 US qt)
With oil filter replacement 1.2 L (1.06 Imp qt, 1.27 US qt)
Total amount 1.4 L (1.23 Imp qt, 1.48 US qt)
Coolant capacity (including all routes): 0.99 L (0.87 Imp qt, 1.05 US qt)
Air filter: Wet type element

2-1
 GENERAL SPECIFICATIONS

Fuel:
Type Premium unleaded gasoline only with a research octane
number of 95 or higher.
Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal)
Reserve 1.1 L (0.24 Imp gal, 0.29 US gal)
Carburetor:
Type FCR-MX37
Manufacturer KEIHIN
Spark plug:
Type/manufacturer
Gap
CR9E/NGK (resistance type)
0.7–0.8 mm (0.028–0.031 in)
2
Clutch type: Wet, multiple-disc
Transmission: USA, CDN, ZA, AUS, NZ EUROPE
Primary reduction system Gear ←
Primary reduction ratio 3.353 (57/17) ←
Final drive Chain ←
Secondary reduction ratio 3.846 (50/13) 3.357 (47/14)
Transmission type Constant mesh, 5-speed ←
Operation Left foot operation ←
Gear ratio:
1st 2.385 (31/13) ←
2nd 1.750 (28/16) ←
3rd 1.353 (23/17) ←
4th 1.095 (23/21) ←
5th 0.895 (17/19) ←
Chassis: USA, CDN, ZA AUS, NZ EUROPE
Frame type Semi double cra- ← ←
dle
Caster angle 27.0 ° 26.6 ° 26.5 °
Trail 115 mm (4.53 in) 114 mm (4.49 in) 113 mm (4.45 in)
Tire:
Type With tube
Size (front) 80/100-21 51M (For USA, CDN and ZA)
90/90-21 M/C 54M M+S (For EUROPE, AUS and NZ)
Size (rear) 100/100-18 59M (For USA, CDN and ZA)
130/90-18 M/C 69M M+S (For EUROPE, AUS and NZ)
Tire pressure (front and rear) 100 kPa (1.0 kgf/cm2, 15 psi)
Brake:
Front brake type Single disc brake
Operation Right hand operation
Rear brake type Single disc brake
Operation Right foot operation
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (link type monocross suspension)

2-2
 MAINTENANCE SPECIFICATIONS

Shock absorber:
Front shock absorber Coil spring/oil damper
Rear shock absorber Coil spring/gas, oil damper
Wheel travel:
Front wheel travel 300 mm (11.8 in)
Rear wheel travel 310 mm (12.2 in)
Electrical:
Ignition system CDI
Generator system AC magneto
Battery type YTZ7S (F)
Battery voltage/capacity 12V/6 AH
Specific gravity 1.310
Headlight type: Quartz bulb (halogen)
Bulb wattage × quantity:
Headlight 12 V 35/36.5 W × 1
Taillight 12 V 1.6/0.3 W × 1
MAINTENANCE SPECIFICATIONS
ENGINE

Item Standard Limit

Cylinder head:
Warp limit ---- 0.05 mm (0.002
in)

Cylinder:
Bore size 77.00–77.01 mm (3.0315–3.0319 in) ----
Out of round limit ---- 0.05 mm (0.002
in)
Camshaft:
Drive method Chain drive (Left) ----
Camshaft cap inside diameter 22.000–22.021 mm (0.8661–0.8670 in) ----
Camshaft outside diameter 21.959–21.972 mm (0.8645–0.8650 in) ----
Shaft-to-cap clearance 0.028–0.062 mm (0.0011–0.0024 in) 0.08 mm (0.003
in)
Cam dimensions

2-3
 MAINTENANCE SPECIFICATIONS

Item Standard Limit

Intake "A" 29.65–29.75 mm (1.1673–1.1713 in) 29.55 mm
(1.1634 in)
Intake "B" 22.45–22.55 mm (0.8839–0.8878 in) 22.35 mm
(0.8799 in)
Exhaust "A" 30.399–30.499 mm (1.1968–1.2007 in) 30.299 mm
(1.1929 in)
Exhaust "B" 22.45–22.55 mm (0.8839–0.8878 in) 22.35 mm
(0.8799 in)
Camshaft runout limit ---- 0.03 mm
(0.0012 in)

Timing chain:
Timing chain type/No. of links 92RH2010-114M/114 ----
Timing chain adjustment method Automatic ----
Valve, valve seat, valve guide:
Valve clearance (cold)
IN 0.10–0.15 mm (0.0039–0.0059 in) ----
EX 0.17–0.22 mm (0.0067–0.0087 in) ----
Valve dimensions:
"A" head diameter (IN) 22.9–23.1 mm (0.9016–0.9094 in) ----
"A" head diameter (EX) 24.4–24.6 mm (0.9606–0.9685 in) ----

"B" face width (IN) 2.26 mm (0.089 in) ----

"B" face width (EX) 2.26 mm (0.089 in) ----

"C" seat width (IN) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630

in)
"C" seat width (EX) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630
in)

2-4
 MAINTENANCE SPECIFICATIONS

Item Standard Limit

"D" margin thickness (IN) 0.8 mm (0.0315 in) ----
"D" margin thickness (EX) 0.7 mm (0.0276 in) ----

Stem outside diameter (IN) 3.975–3.990 mm (0.1565–0.1571 in) 3.945 mm

(0.1553 in)
Stem outside diameter (EX) 4.460–4.475 mm (0.1756–0.1762 in) 4.430 mm
(0.1744 in)
Guide inside diameter (IN) 4.000–4.012 mm (0.1575–0.1580 in) 4.050 mm
(0.1594 in)
Guide inside diameter (EX) 4.500–4.512 mm (0.1772–0.1776 in) 4.550 mm
(0.1791 in)
Stem-to-guide clearance (IN) 0.010–0.037 mm (0.0004–0.0015 in) 0.08 mm (0.003
in)
Stem-to-guide clearance (EX) 0.025–0.052 mm (0.0010–0.0020 in) 0.10 mm (0.004
in)
Stem runout limit ---- 0.01 mm
(0.0004 in)

Valve seat width (IN) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630

in)
Valve seat width (EX) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630
in)
Valve spring:
Free length (IN) 36.58 mm (1.44 in) 35.58 mm (1.40
in)
Free length (EX) 37.54 mm (1.48 in) 36.54 mm (1.44
in)
Set length (valve closed) (IN) 29.13 mm (1.15 in) ----
Set length (valve closed) (EX) 29.30 mm (1.15 in) ----
Compressed force (installed) (IN) 113.00–118.60 N at 29.13 mm (10.50– ----
12.09 kg at 29.13 mm, 23.15–26.66 lb at
1.15 in)
Compressed force (installed) (EX) 126.00–144.00 N at 29.30 mm (12.85– ----
14.68 kg at 29.30 mm, 28.32–32.37 lb at
1.15 in)

2-5
 MAINTENANCE SPECIFICATIONS

Item Standard Limit

Tilt limit* (IN) ---- 2.5°/1.6 mm
(2.5°/0.063 in)
Tilt limit* (EX) ---- 2.5°/1.6 mm
(2.5°/0.063 in)

Direction of winding (top view) (IN) Clockwise ----

Direction of winding (top view) (EX) Clockwise ----
Piston:
Piston to cylinder clearance 0.030–0.055 mm (0.0012–0.0022 in) 0.1 mm (0.004
in)
Piston size "D" 76.955–76.970 mm (3.0297–3.0303 in) ----

Measuring point "H" 8 mm (0.31 in) ----

Piston off-set 0.5 mm (0.020 in)/IN-side ----
Piston pin bore inside diameter 16.002–16.013 mm (0.6300–0.6304 in) 16.043 mm
(0.6316 in)
Piston pin outside diameter 15.991–16.000 mm (0.6296–0.6299 in) 15.971 mm
(0.6288 in)
Piston rings:
Top ring:

Type Barrel ----

Dimensions (B × T) 0.90 × 2.75 mm (0.04 × 0.11 in) ----
End gap (installed) 0.15–0.25 mm (0.006–0.010 in) 0.50 mm (0.020
in)
Side clearance (installed) 0.030–0.065 mm (0.0012–0.0026 in) 0.12 mm (0.005
in)
2nd ring:

Type Taper ----

Dimensions (B × T) 0.80 × 2.75 mm (0.03 × 0.11 in) ----
End gap (installed) 0.30–0.45 mm (0.012–0.018 in) 0.80 mm (0.031
in)
Side clearance (installed) 0.020–0.055 mm (0.0008–0.0022 in) 0.12 mm (0.005
in)

2-6
 MAINTENANCE SPECIFICATIONS

Item Standard Limit

Oil ring:

Dimensions (B × T) 1.50 × 2.25 mm (0.06 × 0.09 in) ----

End gap (installed) 0.10–0.40 mm (0.004–0.016 in) ----
Crankshaft:
Crank width "A" 55.95–56.00 mm (2.203–2.205 in) ----
Runout limit "C" 0.03 mm (0.0012 in) 0.05 mm (0.002
in)
Big end side clearance "D" 0.15–0.45 mm (0.0059–0.0177 in) 0.50 mm (0.02
in)
Small end free play "F" 0.4–1.0 mm (0.016–0.039 in) 2.0 mm (0.08
in)

Clutch:
Friction plate thickness 2.9–3.1 mm (0.114–0.122 in) 2.7 mm (0.106
in)
Quantity 9 ----
Clutch plate thickness 1.1–1.3 mm (0.043–0.051 in) ----
Quantity 8 ----
Warp limit ---- 0.1 mm (0.004
in)
Clutch spring free length 37.0 mm (1.46 in) 36.0 mm (1.42
in)
Quantity 5 ----
Clutch housing thrust clearance 0.10–0.35 mm (0.0039–0.0138 in) ----
Clutch housing radial clearance 0.010–0.044 mm (0.0004–0.0017 in) ----
Clutch release method Inner push, cam push ----
Shifter:
Shifter type Cam drum and guide bar ----
Guide bar bending limit ---- 0.05 mm (0.002
in)
Kickstarter:
Type Kick and ratchet type ----

2-7
 MAINTENANCE SPECIFICATIONS

Item Standard Limit

Carburetor: USA, CDN, ZA,
EUROPE
AUS, NZ
Type/manufacturer FCR-MX37/KEIHIN ← ----
I. D. mark 5UME E0 5UML L0 ----
Main jet (M.J) #170 #160 ----
Main air jet (M.A.J) #115 ← ----
Jet needle (J.N) NJRU NNGU ----
Cutaway (C.A) 1.5 ← ----
Pilot jet (P.J) #42 #45 ----
Pilot air jet (P.A.J) #70 ← ----
Pilot outlet (P.O) ø0.9 ← ----
Bypass (B.P) ø1.0 ← ----
Valve seat size (V.S) ø3.8 ← ----
Starter jet (G.S) #68 ← ----
Leak jet (Acc.P) #70 ← ----
Float height (F.H) 8 mm (0.31 in) ← ----
Engine idle speed 1,750–1,950 r/min ← ----
Intake vacuum 31.3–36.7 kPa ← ----
(235–275 mmHg,
9.25–10.83 inHg)
Hot starter lever free play 3–6 mm (0.12–0.24 ← ----
in)
Lubrication system:
Oil filter type Paper type ----
Oil pump type Trochoid type ----
Tip clearance 0.12 mm or less (0.0047 in or less) 0.20 mm (0.008
in)
Side clearance 0.09–0.17 mm (0.0035–0.0067 in) 0.24 mm (0.009
in)
Housing and rotor clearance 0.03–0.10 mm (0.0012–0.0039 in) 0.17 mm
(0.0067 in)
Cooling:
Radiator core size
Width 120.2 mm (4.73 in) ----
Height 240 mm (9.45 in) ----
Thickness 22 mm (0.87 in) ----
Radiator cap opening pressure 110 kPa (1.1 kg/cm2, 15.6 psi) ----
Radiator capacity (total) 0.54 L (0.48 Imp qt, 0.57 US qt) ----
Water pump
Type Single-suction centrifugal pump ----
CHASSIS

Item Standard Limit

Steering system:
Steering bearing type Taper roller bearing ----

2-8
 MAINTENANCE SPECIFICATIONS

Item Standard Limit

Front suspension:
Front fork travel 300 mm (11.8 in) ----
Fork spring free length 460 mm (18.1 in) 455 mm (17.9
in)
Spring rate, STD K = 4.4 N/mm (0.449 kg/mm, 25.1 lb/in) ----
Optional spring/spacer Yes ----
3
Oil capacity 648 cm (22.8 lmp oz, 21.9 US oz) ----
Oil level 132 mm (5.20 in) ----
<Min.–Max.> (From top of outer tube with inner 95–150 mm (3.74–5.91 in) ----
tube and damper rod fully compressed without
spring.)
Oil grade Suspension oil "S1" ----
Inner tube outer diameter 48 mm (1.89 in) ----
Front fork top end 5 mm (0.20 in) ----
Rear suspension: USA, CDN AUS, NZ, ZA EUROPE
Shock absorber travel 130 mm (5.12 ← ← ----
in)
Spring free length 260 mm (10.24 ← ← ----
in)
Fitting length 249 mm (9.80 245.0 mm (9.65 248.5 mm (9.78 ----
in) in) in)
Preload length
<Min.–Max.> 1.5–22 mm ← ← ----
(0.06–0.87 in)
Spring rate, STD K = 52.0 N/mm ← ← ----
(5.30 kg/mm,
296.8 lb/in)
Optional spring Yes ← ← ----
Enclosed gas pressure 1,000 kPa (10 ← ← ----
kg/cm2, 142
psi)
Swingarm:
Swingarm free play limit
End ---- 1.0 mm (0.04
in)
Wheel: USA, CDN, ZA AUS, NZ, EUROPE
Front wheel type Spoke wheel ← ----
Rear wheel type Spoke wheel ← ----
Front rim size/material 21 × 1.60/Aluminum ← ----
Rear rim size/material 18 × 1.85/Aluminum 18 × 2.15/Aluminum ----
Rim runout limit:
Radial ---- ---- 2.0 mm (0.08
in)
Lateral ---- ---- 2.0 mm (0.08
in)

2-9
 MAINTENANCE SPECIFICATIONS

Item Standard Limit

Drive chain:
Type/manufacturer DID520VM2/DAIDO ----
Number of links 113 links + joint ----
Chain slack 48–58 mm (1.9–2.3 in) ----
Chain length (15 links) ---- 239.3 mm
(9.42 in)
Front disc brake:
Disc outside dia.×Thickness 250 × 3.0 mm (9.84 × 0.12 in) 250 × 2.5 mm
(9.84 × 0.10 in)
Pad thickness 4.4 mm (0.17 in) 1.0 mm (0.04
in)
Master cylinder inside dia. 11.0 mm (0.433 in) ----
Caliper cylinder inside dia. 27.0 mm (1.063 in) × 2 ----
Brake fluid type DOT #4 ----
Rear disc brake:
Disc outside dia.×Thickness 245 × 4.0 mm (9.65 × 0.16 in) 245 × 3.5 mm
(9.65 × 0.14 in)
Deflection limit ---- 0.15 mm
(0.006 in)
Pad thickness 6.4 mm (0.25 in) 1.0 mm (0.04
in)
Master cylinder inside dia. 11.0 mm (0.433 in) ----
Caliper cylinder inside dia. 25.4 mm (1.000 in) × 1 ----
Brake fluid type DOT #4 ----
Brake lever and brake pedal:
Brake lever position 95 mm (3.74 in) ----
Brake pedal height (vertical height above footrest 10 mm (0.39 in) ----
top)
Clutch lever free play (lever end) 8–13 mm (0.31–0.51 in) ----
Throttle grip free play 3–5 mm (0.12–0.20 in) ----
ELECTRICAL

Item Standard Limit

Ignition system:
Advancer type Electrical ----
CDI: USA, CDN AUS, NZ, ZA EUROPE
Pickup coil resistance (color) 248–372 Ωat ← ← ----
20 °C (68 °F)
(White–Red)
CDI unit-model/manufacturer 5UM-E0/ 5UM-F1/ 5UM-L1/ ----
YAMAHA YAMAHA YAMAHA
Ignition coil:
Model/manufacturer 5UL-10/DENSO ----
Minimum spark gap 6 mm (0.24 in) ----
Primary coil resistance 0.08–0.10 Ωat 20 °C (68 °F) ----
Secondary coil resistance 4.6–6.8 kΩat 20 °C (68 °F) ----

2-10
 MAINTENANCE SPECIFICATIONS

Item Standard Limit

Charging system:
System type AC magneto ----
Model (stator)/manufacturer 5UM 30/YAMAHA ----
Normal output 14 V/120 W at 5,000 r/min ----
Charging coil resistance (color) 0.288–0.432 Ω at 20 °C (68 °F) (White–Ground) ----
Lighting coil resistance (color) 0.224–0.336 Ω at 20 °C (68 °F) (Yellow–Ground) ----
Rectifier/regulator:
Regulator type Semiconductor short circuit ----
Model/manufacture SH770AA/SHINDENGEN ----
Regulated voltage (AC) 12.5–13.5 V ----
Regulated voltage (DC) 14.0–15.0 V ----
Rectifier capacity (AC) 12 A ----
Rectifier capacity (DC) 8A ----
Electric starting system:
Type Constant mesh ----
Starter motor:
Model/manufacturer 5UM01/YAMAHA ----
Operation voltage 12 V ----
Output 0.35 kW ----
Armature coil resistance 0.0189–0.0231 Ω at 20 °C (68 °F) ----
Brush overall length 7 mm (0.28 in) 3.5 mm (0.14
in)
Brush quantity 2 pcs. ----
Spring force 3.92–5.88 N (400–600 g, 14.1–21.2 oz) ----
Commutator diameter 17.6 mm (0.69 in) 16.6 mm (0.65
in)
Mica undercut (depth) 1.5 mm (0.06 in) ----
Starter relay:
Model/manufacturer RC19-042/MITSUBA ----
Amperage rating 180 A ----
Coil winding resistance 4.2–4.6 Ω at 20 °C (68 °F) ----
Starting circuit cut-off relay:
Model/manufacturer ACM33221 M38/MATSUSHITA ----
Coil winding resistance 75.69–92.51 Ω at 20 °C (68 °F) ----
Fuse (amperage×quantity):
Main fuse 10 A × 1 ----
Reserve fuse 10 A × 1 ----

2-11
 TIGHTENING TORQUES

TIGHTENING TORQUES
ENGINE

△ - marked portion shall be checked for torque tightening after break-in or before each race.

Thread
Item Q'ty Tightening torque Remarks
size
Spark plug M10S 1 13 Nm (1.3 m•kg, 9.4 ft•lb)
Camshaft cap M6 10 10 Nm (1.0 m•kg, 7.2 ft•lb)
Cylinder head blind plug screw M12 1 28 Nm (2.8 m•kg, 20 ft•lb)
Cylinder head (stud bolt) M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Cylinder head (stud bolt) M8 1 15 Nm (1.5 m•kg, 11 ft•lb)
Cylinder head (bolt) M9 4 38 Nm (3.8 m•kg, 27 ft•lb)
Cylinder head (nut) M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Cylinder head cover M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Cylinder M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Balancer weight M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Balancer shaft driven gear M14 1 50 Nm (5.0 m•kg, 36 ft•lb) Lock washer
Timing chain guide (intake side) M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Timing chain tensioner M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Timing chain tensioner cap bolt M6 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
Impeller M8 1 14 Nm (1.4 m•kg, 10 ft•lb)
Radiator hose clamp M6 10 2 Nm (0.2 m•kg, 1.4 ft•lb)
Copper
Coolant drain bolt M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
washer
Water pump housing M6 4 10 Nm (1.0 m•kg, 7.2 ft•lb)
Radiator stay M6 6 10 Nm (1.0 m•kg, 7.2 ft•lb)
Radiator M6 4 10 Nm (1.0 m•kg, 7.2 ft•lb)
Radiator pipe M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil pump cover M4 1 1.7 Nm (0.17 m•kg, 1.2 ft•lb)
Oil pump M6 3 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil filter element drain bolt M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil filter element cover M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Oil strainer (crankcase) M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Copper
Oil delivery pipe 1 (M10) M10 1 20 Nm (2.0 m•kg, 14 ft•lb)
washer
Copper
Oil delivery pipe 1 (M8) M8 2 18 Nm (1.8 m•kg, 13 ft•lb)
washer
△ Oil hose M6 3 8 Nm (0.8 m•kg, 5.8 ft•lb)
Oil hose clamp — 2 2 Nm (0.2 m•kg, 1.4 ft•lb)
Oil strainer (oil tank) M6 1 9 Nm (0.9 m•kg, 6.5 ft•lb)
Oil tank drain bolt M8 1 18 Nm (1.8 m•kg, 13 ft•lb)
Oil tank (upper) M6 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
Oil tank and frame M6 3 9 Nm (0.9 m•kg, 6.5 ft•lb)
Oil pressure check bolt M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Carburetor joint M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Carburetor joint clamp M4 2 3 Nm (0.3 m•kg, 2.2 ft•lb)
Air filter joint clamp M6 1 3 Nm (0.3 m•kg, 2.2 ft•lb)

2-12
 TIGHTENING TORQUES

Thread
Item Q'ty Tightening torque Remarks
size
Throttle cable adjust bolt and locknut M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Throttle cable (pull) M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Throttle cable (return) M12 1 11 Nm (1.1 m•kg, 8.0 ft•lb)
Throttle cable cover M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Hot starter plunger M12 1 2 Nm (0.2 m•kg, 1.4 ft•lb)
Hot starter cable adjust bolt and locknut M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
△ Air filter case M6 2 8 Nm (0.8 m•kg, 5.8 ft•lb)
Air filter joint and air filter case M5 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Exhaust pipe M8 2 20 Nm (2.0 m•kg, 14 ft•lb)
△ Exhaust pipe protector M6 3 10 Nm (1.0 m•kg, 7.2 ft•lb)
△ Silencer M8 2 30 Nm (3.0 m•kg, 22 ft•lb)
Silencer clamp M8 1 16 Nm (1.6 m•kg, 11 ft•lb)
Spark arrester M5 4 7 Nm (0.7 m•kg, 5.1 ft•lb)
Silencer cap M5 6 5 Nm (0.5 m•kg, 3.6 ft•lb)
Air induction pipe M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Air induction pipe clamp M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Air cut-off valve assembly and bracket M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Bracket (air cut-off valve) and frame M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Crankcase M6 11 12 Nm (1.2 m•kg, 8.7 ft•lb)
Crankcase bearing stopper M6 11 10 Nm (1.0 m•kg, 7.2 ft•lb)
Crankcase bearing stopper (crankshaft) M6 4 14 Nm (1.4 m•kg, 10 ft•lb) Stake.
Left crankcase cover M6 8 10 Nm (1.0 m•kg, 7.2 ft•lb)
Idle gear cover (starter motor) M6 3 10 Nm (1.0 m•kg, 7.2 ft•lb)
Idle gear plate M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Right crankcase cover M6 6 10 Nm (1.0 m•kg, 7.2 ft•lb)
Clutch cover M6 7 10 Nm (1.0 m•kg, 7.2 ft•lb)
Copper
Crankcase oil drain bolt M10 1 20 Nm (2.0 m•kg, 14 ft•lb)
washer
△ Crankshaft end accessing screw M32 1 —
△ Timing mark accessing screw M14 1 —
Drive chain sprocket cover M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Kick shaft ratchet wheel guide M6 2 12 Nm (1.2 m•kg, 8.7 ft•lb) Lock washer
Kickstarter crank M8 1 33 Nm (3.3 m•kg, 24 ft•lb)
Primary drive gear M18 1 75 Nm (7.5 m•kg, 54 ft•lb) Lock washer
Clutch spring M6 5 10 Nm (1.0 m•kg, 7.2 ft•lb)
Clutch boss M16 1 75 Nm (7.5 m•kg, 54 ft•lb) Lock washer
Clutch cable locknut M8 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Push lever shaft M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Drive sprocket M18 1 75 Nm (7.5 m•kg, 54 ft•lb) Lock washer
Drive axle oil seal stopper M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Segment M8 1 30 Nm (3.0 m•kg, 22 ft•lb)
Shift guide M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Stopper lever M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Shift pedal M6 1 12 Nm (1.2 m•kg, 8.7 ft•lb)

2-13
 TIGHTENING TORQUES

CHASSIS

△ - marked portion shall be checked for torque tightening after break-in or before each race.

Thread
Item Q'ty Tightening torque Remarks
size
△ Upper bracket and outer tube M8 4 21 Nm (2.1 m•kg, 15 ft•lb)
△ Lower bracket and outer tube M8 4 21 Nm (2.1 m•kg, 15 ft•lb)
△ Upper bracket and steering stem M24 1 145 Nm (14.5 m•kg, 105 ft•lb)
△ Handlebar upper holder and handlebar
M8 4 28 Nm (2.8 m•kg, 20 ft•lb)
lower holder
△ Handlebar lower holder and upper brack-
M10 2 34 Nm (3.4 m•kg, 24 ft•lb)
et
△ Steering stem and steering ring nut M28 1 Refer to TIP.
Front fork and front fork cap bolt M51 2 30 Nm (3.0 m•kg, 22 ft•lb)
Copper
Front fork and base valve M30 2 55 Nm (5.5 m•kg, 40 ft•lb) washer

Front fork cap bolt and damper rod M12 2 29 Nm (2.9 m•kg, 21 ft•lb)
Front fork bleed screw and front fork cap
M5 2 1 Nm (0.1 m•kg, 0.7 ft•lb)
bolt
△ Front fork and front fork protector M6 6 7 Nm (0.7 m•kg, 5.1 ft•lb)
△ Front fork protector and brake hose hold-
M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
er
Throttle grip cap M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
△ Front brake master cylinder M6 2 9 Nm (0.9 m•kg, 6.5 ft•lb)
Brake lever mounting bolt M6 1 6 Nm (0.6 m•kg, 4.3 ft•lb)
Brake lever mounting nut M6 1 6 Nm (0.6 m•kg, 4.3 ft•lb)
Brake lever position locknut M6 1 5 Nm (0.5 m•kg, 3.6 ft•lb)
△ Front brake hose guide and front brake
M5 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
hose guide bracket
△ Front brake hose guide and lower bracket M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Clutch lever holder M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Clutch lever mounting nut M6 1 4 Nm (0.4 m•kg, 2.9 ft•lb)
Hot starter lever holder M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Hot starter lever mounting nut M5 1 2 Nm (0.2 m•kg, 1.4 ft•lb)
Front brake master cylinder cap M4 2 2 Nm (0.2 m•kg, 1.4 ft•lb)
△ Copper
Front brake hose union bolt M10 2 30 Nm (3.0 m•kg, 22 ft•lb)
washer
△ Front brake caliper M8 2 23 Nm (2.3 m•kg, 17 ft•lb)
△ Front brake caliper and brake hose holder M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Pad pin plug M10 2 3 Nm (0.3 m•kg, 2.2 ft•lb)
△ Front brake caliper and pad pin M10 1 18 Nm (1.8 m•kg, 13 ft•lb)
△ Rear brake caliper and pad pin M10 1 18 Nm (1.8 m•kg, 13 ft•lb)
△ Brake caliper and bleed screw M8 2 6 Nm (0.6 m•kg, 4.3 ft•lb)
△ Front wheel axle and axle nut M16 1 90 Nm (9.0 m•kg, 65 ft•lb)
△ Front wheel axle holder M8 4 21 Nm (2.1 m•kg, 15 ft•lb)
△ Front brake disc M6 6 12 Nm (1.2 m•kg, 8.7 ft•lb)
△ Rear brake disc M6 6 14 Nm (1.4 m•kg, 10 ft•lb)

2-14
 TIGHTENING TORQUES

Thread
Item Q'ty Tightening torque Remarks
size
△ Brake pedal M8 1 26 Nm (2.6 m•kg, 19 ft•lb)
△ Rear brake master cylinder M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Rear brake master cylinder cap M4 2 2 Nm (0.2 m•kg, 1.4 ft•lb)
△ Copper
Rear brake hose union bolt M10 2 30 Nm (3.0 m•kg, 22 ft•lb)
washer
△ Rear wheel axle and axle nut M20 1 125 Nm (12.5 m•kg, 90 ft•lb)
△ Nipple (spoke) — 72 3 Nm (0.3 m•kg, 2.2 ft•lb)
△ Rear wheel sprocket M8 6 50 Nm (5.0 m•kg, 36 ft•lb)
△ Rear brake disc cover M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
△ Rear brake caliper protector M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Drive chain puller adjust bolt and locknut M8 2 19 Nm (1.9 m•kg, 13 ft•lb)
Engine mounting:
△ Engine and engine bracket (front) M10 1 53 Nm (5.3 m•kg, 38 ft•lb)
△ Engine and frame (lower) M10 1 53 Nm (5.3 m•kg, 38 ft•lb)
△ Upper engine bracket and frame M8 4 34 Nm (3.4 m•kg, 24 ft•lb)
△ Lower engine bracket and frame M8 4 34 Nm (3.4 m•kg, 24 ft•lb)
△ Engine and engine bracket (upper) M10 1 55 Nm (5.5 m•kg, 40 ft•lb)
△ Engine guard M6 3 7 Nm (0.7 m•kg, 5.1 ft•lb)
Regulator M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
△ Pivot shaft and nut M16 1 85 Nm (8.5 m•kg, 61 ft•lb)
△ Relay arm and swingarm M14 1 70 Nm (7.0 m•kg, 50 ft•lb)
△ Relay arm and connecting rod M14 1 80 Nm (8.0 m•kg, 58 ft•lb)
△ Connecting rod and frame M14 1 80 Nm (8.0 m•kg, 58 ft•lb)
△ Rear shock absorber and frame M10 1 56 Nm (5.6 m•kg, 40 ft•lb)
△ Rear shock absorber and relay arm M10 1 53 Nm (5.3 m•kg, 38 ft•lb)
△ Rear frame (upper) M8 1 38 Nm (3.8 m•kg, 27 ft•lb)
△ Rear frame (lower) M8 2 32 Nm (3.2 m•kg, 23 ft•lb)
△ Swingarm and brake hose holder M5 4 3 Nm (0.3 m•kg, 2.2 ft•lb)
Swingarm and patch M4 4 2 Nm (0.2 m•kg, 1.4 ft•lb)
Upper drive chain tensioner M8 1 16 Nm (1.6 m•kg, 11 ft•lb)
Lower drive chain tensioner M8 1 16 Nm (1.6 m•kg, 11 ft•lb)
Drive chain support M6 3 7 Nm (0.7 m•kg, 5.1 ft•lb)
Seal guard and swingarm M5 4 6 Nm (0.6 m•kg, 4.3 ft•lb)
△ Fuel tank M6 2 9 Nm (0.9 m•kg, 6.5 ft•lb)
△ Fuel cock M6 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Seat set bracket and fuel tank M6 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
Fuel tank bracket and fuel tank M6 4 7 Nm (0.7 m•kg, 5.1 ft•lb)
△ Air scoop and fuel tank M6 6 7 Nm (0.7 m•kg, 5.1 ft•lb)
△ Air scoop and radiator guard (lower) M6 2 6 Nm (0.6 m•kg, 4.3 ft•lb)
△ Front fender M6 4 7 Nm (0.7 m•kg, 5.1 ft•lb)
△ Rear fender (front) M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
△ Rear fender (rear) M6 2 11 Nm (1.1 m•kg, 8.0 ft•lb)
△ Side cover M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Seat M8 2 22 Nm (2.2 m•kg, 16 ft•lb)

2-15
 TIGHTENING TORQUES

Thread
Item Q'ty Tightening torque Remarks
size
Multi-function display bracket and upper
M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
bracket
Multi-function display M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Plate 1 and front fork protector M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Plate 2 and front fork protector — 2 0.5 Nm (0.05 m•kg, 0.36 ft•lb)
Speed sensor lead holder and lower
M6 1 13 Nm (1.3 m•kg, 9.4 ft•lb)
bracket
Speed sensor lead holder and clamp M6 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
Headlight body and headlight unit — 2 1 Nm (0.1 m•kg, 0.7 ft•lb)
△ Headlight M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Taillight — 3 1 Nm (0.1 m•kg, 0.7 ft•lb)
Taillight lead clamp and rear fender — 3 0.5 Nm (0.05 m•kg, 0.36 ft•lb)
△ Catch tank (upper) M6 1 16 Nm (1.6 m•kg, 11 ft•lb)
△ Catch tank (lower) M6 1 7 Nm (0.7 m•kg, 5.1 ft•lb)
TORX
Footrest bracket and frame M10 4 55 Nm (5.5 m•kg, 40 ft•lb)

Sidestand M10 1 25 Nm (2.5 m•kg, 18 ft•lb)

Front reflector (For CDN) M6 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Rear reflector (For CDN) M5 3 2 Nm (0.2 m•kg, 1.4 ft•lb)

1. First, tighten the steering ring nut approximately 38 Nm (3.8 m•kg, 27 ft•lb) by using the steering nut wrench, then loosen
the steering ring nut one turn.
2. Retighten the steering ring nut 7 Nm (0.7 m•kg, 5.1 ft•lb).

ELECTRICAL

Thread
Item Q'ty Tightening torque Remarks
size
Stator M5 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Holder (AC magneto lead) M5 2 7 Nm (0.7 m•kg, 5.1 ft•lb)
Rotor M12 1 Refer to TIP.
Neutral switch M5 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Starter motor M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)
Starter relay terminal M6 2 4 Nm (0.4 m•kg, 2.9 ft•lb)
Negative lead and cylinder head M6 1 10 Nm (1.0 m•kg, 7.2 ft•lb)
Pickup coil M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb)

Tighten the rotor nut to 65 Nm (6.5 m•kg, 47 ft•lb), loosen and retighten the rotor nut to 65 Nm (6.5 m •kg, 47 ft•lb).

2-16
 TIGHTENING TORQUES

GENERAL TORQUE
SPECIFICATIONS B TORQUE SPECIFI-
A CATION
This chart specifies torque for stan- (Bolt
(Nut)
dard fasteners with standard I.S.O. ) Nm m•kg ft•lb
pitch threads. Torque specifications
10
for special components or assem- 6 mm 6 0.6 4.3
mm
blies are included in the applicable
sections of this book. To avoid warp- 12
8 mm 15 1.5 11
age, tighten multi-fastener assem- A. Distance between flats mm
blies in a crisscross fashion, in B. Outside thread diameter 14 10
progressive stages, until full torque is 30 3.0 22
mm mm
reached. Unless otherwise specified,
17 12
torque specifications call for clean, 55 5.5 40
mm mm
dry threads. Components should be
at room temperature. 19 14
85 8.5 61
mm mm
22 16
130 13 94
mm mm

DEFINITION OF UNITS

Unit Read Definition Measure

-3
mm millimeter 10 meter Length
cm centimeter 10-2 meter Length
kg kilogram 103 gram Weight
2
N Newton 1 kg × m/sec Force
Nm Newton meter N×m Torque
m•kg Meter kilogram m × kg Torque
2
Pa Pascal N/m Pressure
N/mm Newton per millimeter N/mm Spring rate
L Liter — Volume or capacity
cm3 Cubic centimeter — Volume or capacity
r/min Revolution per minute — Engine speed

2-17
 TIGHTENING TORQUES

2-18
 LUBRICATION DIAGRAMS

LUBRICATION DIAGRAMS

1. Oil filter element

2. Oil pump
3. Drive axle
4. Main axle
5. Intake camshaft
6. Exhaust camshaft
7. Oil tank
8. Oil delivery pipe
A. To oil tank

2-19
 LUBRICATION DIAGRAMS

1. Crankshaft
2. Oil filter element
3. Oil tank
4. Oil hose
A. From oil pump

2-20
 CABLE ROUTING DIAGRAM

CABLE ROUTING DIAGRAM

1. Fuel tank breather hose 10. Oil hose 19. Carburetor overflow hose
2. Clamp 11. Clutch cable 20. Catch tank breather hose
3. Diode 12. Starter motor lead 21. Hot starter cable protector
4. Hot starter cable 13. Cable guide 22. Rubber cap
5. Wire harness 14. Negative battery lead
6. Hump (frame) 15. AC magneto lead
7. Cylinder head breather hose 16. Brake hose
8. Throttle position sensor lead 17. Rectifier/regulator lead
9. Neutral switch lead 18. Carburetor breather hose

2-21
 CABLE ROUTING DIAGRAM

A. Insert the end of the fuel tank M. Pass the clutch cable and wire
breather hose into the hole in harness through the cable
the steering stem. guide.
B. Fasten the throttle cable, hot N. Locate the couplers in the frame
starter cable and rectifier/regula- recess.
tor lead onto the frame. Locate O. Pass the carburetor breather
the clamp under the throttle ca- hoses, carburetor overflow hose
ble on the right side of the frame, and catch tank breather hose so
and face its ends, as well as the that the hoses do not contact the
tie ends, downward. rear shock absorber.
C. Fasten the diode (at the mark- P. Secure the coupler by pushing it
ing), throttle cable and hot start- into the hole in the headlight
er cable onto the frame. Locate unit.
the clamp end facing toward the Q. Fasten the throttle position sen-
lower right of the frame and with sor lead and the hot starter ca-
the tie end facing downward. ble.
D. Fasten the wire harness, throttle R. Locate the clamp between the
position sensor lead, starter mo- hot starter cable protector and
tor lead and negative battery rubber cap.
lead onto the frame. Pass the
clamp through the hole in the
stay (air cut-off valve). Locate
the clamp end facing toward the
lower side of the frame and cut
off the tie end.
E. Pass the carburetor breather
hoses, carburetor overflow hose
and catch tank breather hose
between the connecting rod and
cross tube (frame).
F. Fasten the neutral switch lead
and oil hose together with the
plastic locking ties and cut off
the tie ends.
G. Fasten the neutral switch lead
and AC magneto lead onto the
frame. Locate the clamp end
facing toward the outside of the
frame and tie end facing toward
the rear of the frame.
H. Pass the clutch cable through
the cable guide.
I. Fasten the starter motor lead,
AC magneto lead and neutral
switch lead onto the frame. Lo-
cate the clamp end facing to-
ward the rear of the frame and
cut off the tie end.
J. Fasten the clutch cable, starter
motor lead, negative battery
lead, AC magneto lead and neu-
tral switch lead onto the frame.
Locate the clamp end facing to-
ward the rear of the frame and
cut off the tie end.
K. Pass the neutral switch lead and
AC magneto lead on the inside
of the wire harness.
L. Fasten the clutch cable, AC
magneto lead and neutral switch
lead onto the frame. Locate the
clamp end near the clutch cable
and cut off the tie end.

2-22
 CABLE ROUTING DIAGRAM

1. Throttle cable (pull) A. Cross the pull and push throttle D. Pass the carburetor breather
2. Throttle cable (return) cables. hose (of the throttle cable cover)
3. Catch tank hose B. Fasten the catch tank hose and through the hose holder.
4. Ignition coil air induction hose (air cut-off
5. Clamp valve-rear of cylinder head) onto
6. Air induction hose (air cut-off the frame. Locate the clamp end
valve - rear of cylinder head) facing toward the lower side of
7. Catch tank breather hose the frame and cut off the tie end.
C. Fasten the catch tank breather
hose and carburetor breather
hoses together.

2-23
 CABLE ROUTING DIAGRAM

1. Brake master cylinder A. Install the brake hose so that its D. Install the brake hose so that its
2. Brake hose holder pipe portion directs as shown pipe portion directs as shown
3. Brake hose and lightly touches the projec- and lightly touches the projec-
tion on the brake caliper. tion on the brake master cylin-
B. Pass the brake hose into the der.
brake hose holders.
C. If the brake hose contacts the
spring (rear shock absorber),
correct its twist.

2-24
 CABLE ROUTING DIAGRAM

1. Clamp
2. Positive battery lead
3. Battery
4. Negative battery lead
5. Taillight coupler
6. CDI unit coupler (6-pin)
7. CDI unit coupler (3-pin)
8. CDI unit coupler (6-pin)

2-25
 CABLE ROUTING DIAGRAM

A. Fasten the wire harness, nega- M. Fasten the taillight lead to the
tive battery lead and starter mo- rear frame. Locate the clamp
tor lead to the upper engine end facing toward the upper side
bracket (left side). Locate the of the frame and cut off the tie
clamp end facing toward the up- end.
per side of the frame with the tie N. Do not allow the taillight lead to
end cut off on the inside of the slacken.
frame. O. Locate the CDI unit lead be-
B. Fasten the wire harness, nega- tween the CDI unit and rear
tive battery lead and starter mo- fender.
tor lead to the upper engine P. Locate the CDI unit coupler in
bracket (left side). Locate the the clearance between the up-
clamp end facing toward the up- per side of the CDI unit and low-
per side of the frame with the tie er side of the catch tank stay.
end cut off on the inside of the Q. Locate the CDI unit lead be-
frame. Clamp the wire harness tween the CDI unit and rear
and negative lead at the mark- frame.
ing.
C. Pass the starter motor lead
through the hole in the relay
holder.
D. Fit the cover securely.
E. Connect the wire harness to the
starter relay.
F. Fasten the catch tank breather
hose and catch tank hose to the
rear frame. Clamp them close to
where they are joined to the
frame. Fasten the pipe tightly
enough not to crush it. Locate
the clamp end facing toward the
rear of the frame with the tie end
facing downward.
G. Fasten the (three) CDI unit leads
and taillight lead to the rear
frame. Locate the clamp end
facing toward the upper side of
the frame and cut off the tie end.
H. Connect the negative battery
lead to the battery negative ter-
minal.
I. Connect the negative battery
lead to the wire harness.
J. Fasten the wire harness to the
rear frame. Locate the clamp
end facing toward the upper side
of the frame and the tie end to-
ward the inside of the frame.
Clamp the wire harness at the
marking.
K. Pass the wire harness, starter
relay lead, starting circuit cut-off
relay lead and negative battery
lead through the hole in the relay
holder.
L. Fasten the (three) CDI unit leads
and taillight lead to the rear
frame. Locate the clamp end
facing toward the lower side of
the frame and cut off the tie end.

2-26
 CABLE ROUTING DIAGRAM

1. Throttle cable 12. Upper bracket

2. Clamp 13. Clutch switch coupler
3. Brake hose 14. Engine stop switch coupler
4. Clutch cable 15. Multi-function display coupler
5. Hose guide 16. Start switch coupler
6. Main switch coupler 17. Speed sensor coupler
7. Wire harness 18. Speed sensor lead
8. Headlight coupler
9. Hot starter cable
10. Multi-function display bracket
11. Main switch

2-27
 CABLE ROUTING DIAGRAM

A. Fasten the start switch lead to

the handlebar with the plastic
bands.
B. Fasten the engine stop switch
lead and clutch switch lead to
the handlebar with the plastic
bands.
C. Pass the brake hose through
the hose guides.
D. Secure the coupler by inserting
it into the multi-function display
bracket.
E. Pass the throttle cables, clutch
cable and hot starter cable be-
tween the upper bracket and
multi-function display bracket.
F. Fasten the multi-function display
leads to the bracket. Cut off the
tie end.
G. Secure the coupler by pushing it
into the hole in the multi-function
display bracket.
H. Secure the wire harness clip by
pushing it into the hole in the
multi-function display bracket on
the inside.
I. Fasten the wire harness to the
multi-function display bracket.
Cut off the tie end.
J. Fasten the main switch lead
(wire harness side) to the multi-
function display bracket. Locate
the clamp end facing toward the
lower side of the frame and cut
off the tie end.
K. Pass the speed sensor lead
through the guide on the outside
of the front fork.

2-28
 PERIODIC MAINTENANCE CHART FOR THE EMISSION
CONTROL SYSTEM (For Canada)
REGULAR INSPECTION AND ADJUSTMENTS
PERIODIC MAINTENANCE CHART FOR THE EMISSION CONTROL SYSTEM (For Canada)

• From 4,200 mi (7,000 km) or 9 months, repeat the maintenance intervals starting from 1,800 mi (3,000 km) or 3 months.
• Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and technical
skills.

ODOMETER
INITIAL
READINGS

No. ITEM CHECKS AND MAINTENANCE JOBS 600 mi 1,800 mi 3,000 mi

(1,000 (3,000 (5,000
km) or 1 km) or 3 km) or 6
month months months
Check fuel hoses for cracks or damage.
1 * Fuel line   
Replace if necessary.
Check condition.
2 Spark plug   
Adjust gap and clean.
Check and adjust valve clearance when en-
3 * Valve clearance   
gine is cold.
Clean with solvent and apply foam air-filter oil
4 * Air filter element or equivalent oil.   
Replace if necessary.
Check ventilation hose for cracks or damage
5 * Breather system and drain any deposits.   
Replace if necessary.
Check engine idling speed and starter opera-
6 * Carburetor tion.   
Adjust if necessary.
Check for leakage.
7 Exhaust system Tighten if necessary.   
Replace gasket(s) if necessary.
8 Engine oil Change (warm engine before draining).   
9 Engine oil filter element Replace.   
10 Engine oil strainer Clean.   
Check the hose for damage.
11 * Air induction system  
Replace any damaged parts if necessary.

3-1
 GENERAL MAINTENANCE AND LUBRICATION CHART (For
Canada)
GENERAL MAINTENANCE AND LUBRICATION CHART (For Canada)
ODOMETER
INITIAL
READINGS

No. ITEM CHECKS AND MAINTENANCE JOBS 600 mi 1,800 mi 3,000 mi

(1,000 (3,000 (5,000
km) or 1 km) or 3 km) or 6
month months months
Check operation.
1 Clutch   
Adjust or replace cable.
Check hoses for cracks of damage.
  
Replace if necessary.
2 * Cooling system
Replace with ethylene glycol anti-freeze cool-
Every 1 year
ant every 1 year.
3 * Spark arrester Clean. 

3
Check operation, fluid level, and for fluid leak-
age.   
4 * Front brake
Replace brake pads if necessary.
Replace brake fluid every 1 year. Every 1 year
Check operation, fluid level, and for fluid leak-
age.   
5 * Rear brake
Replace brake pads if necessary.
Replace brake fluid every 1 year. Every 1 year
Check for cracks or damage.  
6 * Brake hoses
Replace. Every 4 years
Check runout, spoke tightness and for dam-
7 * Wheels age.   
Tighten spokes if necessary.
Check tread depth and for damage.
Replace if necessary.
8 * Tires   
Check air pressure.
Correct if necessary.
Check bearings for smooth operation.
9 * Wheel bearings   
Replace if necessary.
Check bearing assemblies for looseness.
10 * Swingarm pivot bearings Moderately repack with lithium-soapbased   
grease.
Check chain slack/alignment and condition.
11 Drive chain Adjust and lubricate chain with a special O-ring Every ride
chain lubricant thoroughly.
Check bearing assemblies for looseness.

12 * Steering bearings Moderately repack with lithium-soapbased   

grease every 1,200 mi (2,000 km) or 12
months (whichever comes first).
Brake and clutch lever pivot Apply lithium-soap-based grease (all-purpose
13   
shafts grease) lightly.
Apply lithium-soap-based grease (all-purpose
14 Brake pedal pivot shafts   
grease) lightly.

3-2
 MAINTENANCE INTERVALS FOR COMPETITION USE

ODOMETER
INITIAL
READINGS

No. ITEM CHECKS AND MAINTENANCE JOBS 600 mi 1,800 mi 3,000 mi

(1,000 (3,000 (5,000
km) or 1 km) or 3 km) or 6
month months months
Check operation.
15 Sidestand pivot Apply lithium-soap-based grease (all-purpose   
grease) lightly.
Check operation and for oil leakage.
16 * Front fork  
Replace if necessary.
Check operation and for oil leakage.
17 * Shock absorber assembly  
Replace if necessary.
18 * Rear suspension link pivots Apply molybdenum disulfide grease lightly.  
Apply Yamaha chain and cable lube or engine
19 * Control cables   
oil 10W-30 thoroughly.
Check operation and free play.
20 * Throttle grip housing and cable Adjust the throttle cable free play if necessary.   
Lubricate the throttle grip housing and cable.
Check all chassis fitting and fasteners.
21 * Chassis fasteners   
Correct if necessary.
22 Battery Check terminal for looseness and corrosion.  

• The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
• Hydraulic brake service
• After disassembling the brake master cylinders and calipers, always change the fluid. Regularly check the brake fluid
levels and fill the reservoirs as required.
• Every two years replace the internal components of the brake master cylinders and calipers, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.

MAINTENANCE INTERVALS FOR COMPETITION USE

• The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind that such factors as
weather, terrain, geographical location, and individual usage will alter the required maintenance and lubrication intervals.
If you are a doubt as to what intervals to follow in maintaining and lubricating your machine, consult your Yamaha dealer.
• Periodic inspection is essential in making full use of the machine performance. The service life of the parts varies sub-
stantially according to the environment in which the machine runs (e.g., rain, dirt, etc.). Therefore, earlier inspection is
required by reference to the list below.

Every Every
After
Every third fifth (or As re-
Item break- Remarks
race (or 500 1,000 quired
in
km) km)
ENGINE OIL
Replace ● ●
VALVES
Check the valve clearances ● ● The engine must be cold.
Inspect ● Check the valve seats and valve
stems for wear.
Replace ●
VALVE SPRINGS
Inspect ● Check the free length and the tilt.
Replace ●

3-3
 MAINTENANCE INTERVALS FOR COMPETITION USE

Every Every
After
Every third fifth (or As re-
Item break- Remarks
race (or 500 1,000 quired
in
km) km)
VALVE LIFTERS
Inspect ● Check for scratches and wear.
Replace ●
CAMSHAFTS Inspect the camshaft surface.
Inspect ● Inspect the decompression system.
Replace ●
CAMSHAFT SPROCKETS
Inspect ● Check for wear on the teeth and for
damage.
Replace ●
PISTON
Inspect ● ● Inspect crack.
Clean ● Inspect carbon deposits and eliminate
them.
Replace ● It is recommended that the piston pin
and ring are also replaced at the same
time.
PISTON RING
Inspect ● Check ring end gap.
Replace ● ●
PISTON PIN
Inspect ●
Replace ●
CYLINDER HEAD Inspect carbon deposits and eliminate
them.
Inspect and clean ● Change gasket.
CYLINDER
Inspect and clean ● Inspect score marks.
Replace ● Inspect wear.
CLUTCH
Inspect and adjust ● ● Inspect housing, friction plate, clutch
plate and spring.
Replace ●
TRANSMISSION
Inspect ●
Replace bearing ●
SHIFT FORK, SHIFT CAM,
GUIDE BAR
Inspect ● Inspect wear.
ROTOR NUT
Retighten ● ●
MUFFLER
Inspect and retighten ● ●
Clean ●
Replace ●

3-4
 MAINTENANCE INTERVALS FOR COMPETITION USE

Every Every
After
Every third fifth (or As re-
Item break- Remarks
race (or 500 1,000 quired
in
km) km)
CRANK
Inspect and clean ● ●
CARBURETOR
Inspect, adjust and clean ● ●
AIR INDUCTION SYSTEM
Inspect and clean ● ● ● ●
SPARK PLUG
Inspect and clean ● ●
Replace ●
DRIVE CHAIN Use chain lube.
Lubricate, slack, alignment ● ● Chain slack: 48–58 mm (1.9–2.3 in)
Replace ●
COOLING SYSTEM
Check coolant level and leakage ● ●
Check radiator cap operation ●
Replace coolant ● Every two years
Inspect hoses ●
OUTSIDE NUTS AND BOLTS
Retighten ● ● Refer to "STARTING AND BREAK-
IN" section in the CHAPTER 1.
AIR FILTER
Clean and lubricate ● ● Use foam air-filter oil or equivalent oil.
Replace ●
OIL FILTER
Replace ● ●
ENGINE GUARD
Replace ● Breakage
FRAME
Clean and inspect ● ●
FUEL TANK, COCK
Clean and inspect ● ●
BRAKES
Adjust lever position and pedal ● ●
height
Lubricate pivot point ● ●
Check brake disc surface ● ●
Check fluid level and leakage ● ●
Retighten brake disc bolts, cali- ● ●
per bolts, master cylinder bolts
and union bolts
Replace pads ●
Replace brake fluid ● Every one year

3-5
 MAINTENANCE INTERVALS FOR COMPETITION USE

Every Every
After
Every third fifth (or As re-
Item break- Remarks
race (or 500 1,000 quired
in
km) km)
FRONT FORKS
Inspect and adjust ● ●
Replace oil ● ● Suspension oil "S1"
Replace oil seal ●
FRONT FORK OIL SEAL AND
DUST SEAL
Clean and lube ● ● Lithium base grease
PROTECTOR GUIDE
Replace ●
REAR SHOCK ABSORBER
Inspect and adjust ● ●
(After
rain
Lube ● ride) ● Molybdenum disulfide grease
Retighten ● ●
DRIVE CHAIN GUIDE AND
ROLLERS
Inspect ● ●
SWINGARM
Inspect, lube and retighten ● ● Molybdenum disulfide grease
RELAY ARM, CONNECTING
ROD
Inspect, lube and retighten ● ● Molybdenum disulfide grease
SIDESTAND
Lubricate ● Lithium base grease
STEERING HEAD
Inspect free play and retighten ● ●
Clean and lube ● Lithium base grease
Replace bearing ●
TIRE, WHEELS
Inspect air pressure, wheel run- ● ●
out, tire wear and spoke loose-
ness
Retighten sprocket bolt ● ●
Inspect bearings ●
Replace bearings ●
Lubricate ● Lithium base grease
THROTTLE, CONTROL CABLE
Check routing and connection ● ●
Lubricate ● ● Yamaha cable lube or SAE 10W-40
motor oil
HOT STARTER, CLUTCH LEVER
Inspect free play ●
BATTERY
Check terminal for looseness ●
and corrosion

3-6
 PRE-OPERATION INSPECTION AND MAINTENANCE

PRE-OPERATION INSPECTION AND MAINTENANCE

Before riding for break-in operation or practice, make sure the machine is in good operating condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE

Item Routine Page

Check that coolant is filled up to the radiator cap. Check the cool-
Coolant P.3-11 – 12
ing system for leakage.
Check that a fresh gasoline is filled in the fuel tank. Check the fuel
Fuel P.1-18
line for leakage.
Check that the oil level is correct. Check the crankcase and oil
Engine oil P.3-14 – 15
line for leakage.
Check that gears can be shifted correctly in order and that the
Gear shifter and clutch P.3-12 – 13
clutch operates smoothly.
Check that the throttle grip operation and free play are correctly
Throttle grip/Housing P.3-13
adjusted. Lubricate the throttle grip and housing, if necessary.
Brakes Check the play of front brake and effect of front and rear brake. P.3-19 – 22
Check drive chain slack and alignment. Check that the drive chain
Drive chain P.3-22 – 23
is lubricated properly.
Check for excessive wear and tire pressure. Check for loose
Wheels P.3-26 – 27
spokes and have no excessive play.
Check that the handlebar can be turned smoothly and have no ex-
Steering P.3-27
cessive play.
Front forks and rear shock Check that they operate smoothly and there is no oil leakage.
P.3-23 – 26
absorber
Check that the clutch and throttle cables move smoothly. Check
Cables (wires) that they are not caught when the handlebars are turned or when —
the front forks travel up and down.
Exhaust pipe Check that the exhaust pipe is tightly mounted and has no cracks. P.3-10 – 11
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-22
Lubrication Check for smooth operation. Lubricate if necessary. P.3-28
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-20
Check that the AC magneto, CDI unit, and ignition coil are con-
Lead connectors P.1-7
nected tightly.
Is the machine set suitably for the condition of the course and
Settings weather or by taking into account the results of test runs before P.4-1 – 10
riding? Are inspection and maintenance completely done?

3-7
 ENGINE

ENGINE
REMOVING THE SEAT, FUEL TANK AND SIDE COVERS

Order Part name Q'ty Remarks

Turn the fuel cock to "OFF".
Disconnect the fuel hose.
1 Seat 1
2 Air scoop (left and right) 2
3 Bolt (fuel tank) 2
4 Fuel tank 1
5 Left side cover 1 Open the air filter case cover.
6 Right side cover 1 Refer to removal section.
7 Headlight coupler 1
8 Headlight 1

3-8
 ENGINE

REMOVING THE SIDE COVER

1. Remove:
• Bolt (side cover)
• Right side cover "1"

Draw the side cover backward to re-

move it because its claw "a" is insert-
ed in the air filter case.

3-9
 ENGINE

REMOVING THE EXHAUST PIPE AND SILENCER

Order Part name Q'ty Remarks

Refer to "REMOVING THE SEAT, FUEL
Right side cover
TANK AND SIDE COVERS" section.
1 Bolt (silencer clamp) 1 Only loosening.
2 Bolt [silencer (front)] 1
3 Bolt [silencer (rear)] 1
4 Collar 1
5 Silencer 1
6 Silencer clamp 1
7 Nut (exhaust pipe) 2
8 Exhaust pipe 1
9 Gasket 2

3-10
 ENGINE

CHECKING THE SILENCER AND CHECKING THE COOLANT LEVEL CHANGING THE COOLANT
EXHAUST PIPE
1. Inspect:
• Gasket "1" Do not remove the radiator cap Do not remove the radiator cap
Damage → Replace. "1", drain bolt and hoses when the when the engine is hot.
engine and radiator are hot. Scald-
ing hot fluid and steam may be
blown out under pressure, which Take care so that coolant does not
could cause serious injury. When splash on painted surfaces. If it
the engine has cooled, place a splashes, wash it away with water.
thick towel over the radiator cap,
slowly rotate the cap counter- 1. Place a container under the en-
clockwise to the detent. This pro- gine.
INSTALLING THE SILENCER AND cedure allows any residual 2. Remove:
EXHAUST PIPE pressure to escape. When the • Seat
1. Install: hissing sound has stopped, press • Left side cover
• Gasket down on the cap while turning 3. Remove the catch tank hose from
• Exhaust pipe "1" counterclockwise and remove it. the catch tank and drain the tank
• Nut (exhaust pipe) "2" of its coolant.
4. Remove:
Nut (exhaust pipe): • Coolant drain bolt "1"
20 Nm (2.0 m•kg, 14 Hard water or salt water is harmful
ft•lb) to the engine parts. You may use
distilled water, if you can't get soft
water.
First, temporarily install both nuts,
then tighten either of these nuts to 13
Nm (1.3 m•kg, 9.4 ft•lb) and the other
to 20 Nm (2.0 m•kg, 14 ft•lb), and
then come back to the first one and
5. Remove:
retighten it to 20 Nm (2.0 m•kg, 14
• Radiator cap
ft•lb).
Drain the coolant completely.
6. Clean:
1. Place the machine on a level • Cooling system
place, and hold it in an upright po- Thoroughly flush the cooling sys-
sition. tem with clean tap water.
2. Remove: 7. Install:
• Radiator cap • Copper washer
3. Check: • Coolant drain bolt
• Coolant level "a" Coolant drain bolt:
2. Install: Coolant level low → Add coolant. 10 Nm (1.0 m•kg, 7.2
• Silencer clamp "1" ft•lb)
Silencer clamp:
8. Fill:
16 Nm (1.6 m•kg, 11
• Radiator
ft•lb)
• Engine
• Gasket "2" To specified level.
• Silencer "3" Recommended coolant:
• Washer "4" High quality ethylene
• Bolt (silencer) "5" 1. Radiator glycol anti-freeze con-
Bolt (silencer): taining anti-corrosion
30 Nm (3.0 m•kg, 22 for aluminum engine
ft•lb) Coolant "1" and water
(soft water) "2" mixing ra-
tio:
50%/50%
Coolant capacity:
0.99 L (0.87 Imp qt, 1.05
US qt)

3-11
 ENGINE

CHECKING THE RADIATOR CAP

OPENING PRESSURE • Do not apply pressure more than
• Do not mix more than one type of 1. Attach: specified pressure.
ethylene glycol antifreeze con- • Radiator cap tester "1" and adapt- • Radiator should be filled fully.
taining corrosion inhibitors for er "2"
aluminum engine. 4. Inspect:
• Do not use water containing im- Radiator cap tester:
• Pressure
purities or oil. YU-24460-01/90890-
Impossible to maintain the speci-
01325
fied pressure for 10 seconds →
Radiator cap tester
Repair.
adapter:
• Radiator "1"
YU-33984/90890-01352
• Radiator hose joint "2"
Coolant leakage → Repair or re-
Apply water on the radiator cap seal. place.
• Radiator hose "3"
Swelling → Replace.

Handling notes of coolant:

The coolant is harmful so it should be
handled with special care.

• When coolant splashes to your

3. Radiator cap
eye.
2. Apply the specified pressure. ADJUSTING THE CLUTCH LEVER
Thoroughly wash your eye with
Radiator cap opening FREE PLAY
water and see your doctor.
pressure: 1. Check:
• When coolant splashes to your
110 kPa (1.1 kg/cm2, • Clutch lever free play "a"
clothes.
15.6 psi) Out of specification → Adjust.
Quickly wash it away with water
and then with soap. Clutch lever free play "a"
3. Inspect:
• When coolant is swallowed. :
• Pressure
Quickly make him vomit and take 8–13 mm (0.31–0.51 in)
Impossible to maintain the speci-
him to a doctor. fied pressure for 10 seconds →
Replace.
CHECKING THE COOLING
9. Install:
SYSTEM
• Radiator cap
1. Inspect:
Start the engine and warm it up
• Coolant level
for a several minutes.
2. Attach:
10. Check:
• Radiator cap tester "1" and adapt-
• Coolant level
er "2" 2. Adjust:
Coolant level low → Add coolant.
• Clutch lever free play
CHECKING THE RADIATOR CAP Radiator cap tester:
1. Inspect: YU-24460-01/90890-
• Seal (radiator cap) "1" 01325 Clutch lever free play adjustment
• Valve and valve seat "2" Radiator cap tester steps:
Crack/damage → Replace. adapter: a. Loosen the locknuts "1".
Exist fur deposits "3" → Clean or YU-33984/90890-01352 b. Adjust the free play by changing
replace. their tightening position.
c. Tighten the locknuts.
Locknut:
7 Nm (0.7 m•kg, 5.1
ft•lb)

3. Apply the specified pressure. • Make minute adjustment on the le-

ver side using the adjuster "2".
Standard pressure: • After adjustment, check proper op-
180 kPa (1.8 kg/cm2, eration of clutch lever.
25.6 psi)

3-12
 ENGINE

LUBRICATING THE THROTTLE

1. Remove:
• Cover (throttle cable cap) "1"
• Cover (grip cap) "2"
• Throttle grip cap "3"

ADJUSTING THE THROTTLE GRIP

FREE PLAY
CLEANING THE AIR FILTER
1. Check:
ELEMENT
• Throttle grip free play "a"
Out of specification → Adjust.
2. Apply: Proper air filter maintenance is the
Throttle grip free play biggest key to preventing premature
"a": • Lithium soap base grease
On the throttle cable end "a". engine wear and damage.
3–5 mm (0.12–0.20 in)

Never run the engine without the

air filter element in place; this
would allow dirt and dust to enter
the engine and cause rapid wear
and possible engine damage.

3. Install: 1. Open the air filter case cover "1"

2. Adjust: • Throttle grip cap
• Throttle grip free play • Screw (throttle grip cap) Loosen the quick screw "2" and pull
on it to open the air filter case cover.
Screw (throttle grip cap):
Adjustment steps: 4 Nm (0.4 m•kg, 2.9
a. Slide the adjuster cover. ft•lb)
b. Loosen the locknut "1".
c. Turn the adjuster "2" until the • Cover (grip cap)
specified free play is obtained. • Cover (throttle cable cap)
d. Tighten the locknut. ADJUSTING THE HOT STARTER
LEVER FREE PLAY
Locknut:
1. Check:
4 Nm (0.4 m•kg, 2.9
• Hot starter lever free play "a" 2. Unhook:
ft•lb)
Out of specification → Adjust. • Binder "1"
Hot starter lever free play
Prior to adjusting throttle grip free "a":
play, the engine idling speed should 3–6 mm (0.12–0.24 in)
be adjusted.
2. Adjust:
• Hot starter lever free play

After adjusting the throttle grip

free play, turn the handlebar to the Hot starter lever free play adjust-
right and to the left to ensure that ment steps: 3. Remove:
this does not cause the engine a. Loosen the locknut "1". • Air filter element "1"
idling speed to change. b. Turn the adjuster "2" until free • Air filter guide "2"
play "a" is within the specified lim-
its.
c. Tighten the locknut.
Locknut:
4 Nm (0.4 m•kg, 2.9
ft•lb)

After adjustment, check proper oper-

ation of hot starter.

3-13
 ENGINE

4. Clean:
• Air filter element Recommended brand:
Clean them with solvent. YAMALUBE
Recommended engine
oil type
After cleaning, remove the remaining
SAE 10W-30, SAE 10W-
solvent by squeezing the element.
40, SAE 10W-50, SAE
15W-40, SAE 20W-40 or
9. Hook: SAE 20W-50
• Do not twist the element when Recommended engine
• Binder "1"
squeezing the element. oil grade
• Leaving too much of solvent in API service SG type or
the element may result in poor Hook the binder "1" so that it contacts
higher, JASO standard
starting. the filter guide projections "a".
MA

5. Inspect: CHECKING THE ENGINE OIL 4. Install:

• Air filter element LEVEL • Oil tank cap
Damage → Replace. 1. Start the engine, warm it up for 5. Start the engine and let it warm up
6. Apply: several minutes, and then turn off for several minutes.
• Foam-air-filter oil or equivalent oil the engine and wait for five min- 6. Turn off the engine and inspect
to the element utes. the oil level once again.
2. Place the machine on a level
place and hold it up on upright po-
• Squeeze out the excess oil. Ele- Wait a few minutes until the oil settles
sition by placing the suitable
ment should be wet but not drip- before inspecting the oil level.
stand under the engine.
ping.
3. Inspect: CHANGING THE ENGINE OIL
• Wipe off the oil left on the element
• Oil level 1. Start the engine and warm it up
surface using a clean dry cloth. (Ex-
Oil should be up to the full level in for several minutes, and then turn
cess oil in the element may ad-
the check window "1". off the engine and wait for five
versely affect engine starting.)
Level check window is not full. → minute.
7. Install: Add 0.2 L (0.18 Imp qt, 0.21 US 2. Place the machine on a level
• Air filter guide "1" qt) of oil. place and hold it on upright posi-
tion by placing the suitable stand
• Align the projection "a" on filter under the engine.
guide with the hole "b" in air filter el- 3. Place a suitable container under
ement. the engine.
• Apply the lithium soap base grease 4. Remove:
on the matching surface "c" on air • Engine guard "1"
filter element. • Bolt (oil tank) "2"
• Washer "3"
• Oil filler cap "4"
• Engine oil also lubricates the • Oil tank drain bolt "5"
clutch and the wrong oil types or • Crankcase oil drain bolt "6"
additives could cause clutch • Oil filter element drain bolt "7"
slippage. Therefore, do not add Drain the crankcase and oil tank
any chemical additives or use en- of its oil.
gine oils with a grade of CD or
8. Install: higher and do not use oils la-
• Air filter element "1" beled "ENERGY CONSERVING
II".
• Do not allow foreign materials to
Align the projection "a" on filter guide
enter the crankcase.
with the hole "b" in air filter case.

3-14
 ENGINE

• Oil strainer "2"

Oil strainer:
9 Nm (0.9 m•kg, 6.5
ft•lb)
• Oil hose
• Bolt (oil hose)
Bolt (oil hose):
8 Nm (0.8 m•kg, 5.8 11. Check:
ft•lb) • Oil leakage
12. Install:
• Oil hose clamp • Oil filler cap
Oil hose clamp: • Washer (oil tank)
2 Nm (0.2 m•kg, 1.4 • Bolt (oil tank)
ft•lb) Bolt (oil tank):
7 Nm (0.7 m•kg, 5.1
5. Remove: ft•lb)
• Oil hose clamp "1"
• Bolt (oil hose) 13. Check:
• Oil hose "2" • Engine oil level
• Oil strainer "3" CHECKING THE OIL PRESSURE
1. Check:
• Oil pressure
9. Install:
• Copper washer Checking steps:
• Oil filter element drain bolt a. Slightly loosen the oil pressure
check bolt "1".
Oil filter element drain b. Start the engine and keep it idling
bolt: until oil starts to seep from the oil
6. Inspect: 10 Nm (1.0 m•kg, 7.2 pressure check bolt. If no oil
• Oil strainer ft•lb) comes out after one minute, turn
Clogged → Blow.
• Crankcase oil drain bolt the engine off so it will not seize.
7. If the oil filter is to be replaced dur-
c. Check oil passages and oil pump
ing this oil change, remove the fol- Crankcase oil drain bolt:
for damage or leakage.
lowing parts and reinstall them. 20 Nm (2.0 m•kg, 14
d. Start the engine after solving the
ft•lb)
problem(s) and recheck the oil
Replacement steps: • Oil tank drain bolt pressure.
a. Remove the oil filter element cov- e. Tighten the oil pressure check
er "1" and oil filter element "2". Oil tank drain bolt:
bolt.
b. Check the O-rings "3", if cracked 18 Nm (1.8 m•kg, 13
ft•lb) Oil pressure check bolt:
or damaged, replace them with a
10 Nm (1.0 m•kg, 7.2
new one. • Engine guard ft•lb)
c. Install the oil filter element and oil
Engine guard:
filter element cover.
7 Nm (0.7 m•kg, 5.1
Oil filter element cover: ft•lb)
10 Nm (1.0 m•kg, 7.2
ft•lb) 10. Fill:
• Engine oil
Oil quantity:
Periodic oil change:
1.1 L (0.97 Imp qt, 1.16
US qt)
With oil filter replace-
ment:
1.2 L (1.06 Imp qt, 1.27
US qt)
Total amount:
8. Install: 1.4 L (1.23 Imp qt, 1.48
• O-ring "1" US qt)

3-15
 ENGINE

ADJUSTING THE PILOT SCREW 4. Remove:

(For EUROPE) • Timing mark accessing screw "1"
1. Adjust: • Crankshaft end accessing screw
• Pilot screw "1" "2"
• O-ring
Adjustment steps:

To optimize the fuel flow at a smaller

throttle opening, each machine's pilot
screw has been individually set at the
factory. Before adjusting the pilot
screw, turn it in fully and count the
number of turns. Record this number
5. Check:
as the factory-set number of turns
• Valve clearance
out.
Out of specification → Adjust.
a. Turn in the pilot screw until it is Valve clearance (cold):
lightly seated. ADJUSTING THE VALVE Intake valve:
b. Turn out the pilot screw by the CLEARANCE 0.10–0.15 mm
factory-set number of turns. (0.0039–0.0059 in)
Pilot screw (example): This section is intended for those who Exhaust valve:
2 turns out have basic knowledge and skill con- 0.17–0.22 mm
cerning the servicing of Yamaha mo- (0.0067–0.0087 in)
torcycles (e.g., Yamaha dealers,
service engineers, etc.) Those who
Checking steps:
have little knowledge and skill con-
a. Turn the crankshaft counterclock-
cerning servicing are requested not to
wise with a wrench.
undertake inspection, adjustment,
b. Align the T.D.C. mark "a" on the
disassembly, or reassembly only by
rotor with the align mark "b" on the
reference to this manual. It may lead
crankcase cover when piston is at
to servicing trouble and mechanical
T.D.C. on compression stroke.
damage.
ADJUSTING THE ENGINE IDLING
SPEED
1. Start the engine and thoroughly • The valve clearance should be ad-
warm it up. justed when the engine is cool to
2. Adjust: the touch.
• Engine idling speed • The piston must be at Top Dead
Center (T.D.C.) on compression
stroke to check or adjust the valve
Adjustment steps:
clearance.
a. Turn the throttle stop screw "1" In order to be sure that the piston is at
until the specified engine idling 1. Remove: Top Dead Center, the punch mark "c"
speed. • Seat on the exhaust camshaft and the
• Fuel tank punch mark "d" on the intake cam-
Using a digital engine tachometer for Refer to "SEAT, FUEL TANK shaft must align with the cylinder
idle speed adjustment, detect the en- AND SIDE COVERS" section. head surface, as shown in the illustra-
gine idling speed by bringing the 2. Drain: tion.
sensing element "c" of the engine ta- • Coolant
chometer close to the ignition coil "2". Refer to "CHANGING THE
COOLANT" section.
To increase idle speed→Turn the 3. Remove:
throttle stop screw "1" in "a". • Right radiator
To decrease idle speed→Turn the Right to "RADIATOR" section in
throttle stop screw "1" out "b". the CHAPTER 5.
• Carburetor
Engine idling speed: Refer to "CARBURETOR" section
1,750–1,950 r/min in the CHAPTER 5. c. Measure the valve clearance "e"
• Spark plug using a feeler gauge "1".
• Upper engine bracket
• Cylinder head cover Record the measured reading if the
Refer to "CAMSHAFTS" section clearance is incorrect.
in the CHAPTER 5.

3-16
 ENGINE

g. Install the camshafts (exhaust

The thickness "a" of each pad is indi- and intake).
cated in hundredths of millimeters on Refer to "CAMSHAFTS" section
the pad upper surface. in the CHAPTER 5.

d. Round off the last digit of the in-

stalled pad number to the nearest
increment.
Last digit of pad
Rounded valve
6. Adjust: number
• Valve clearance 0, 1 or 2 0
4, 5 or 6 5
Adjustment steps:
a. Remove the camshaft (intake and 8 or 9 10
exhaust). EXAMPLE:
Refer to "CAMSHAFTS" section Installed pad number = 148
in the CHAPTER 5. Rounded off value = 150
b. Remove the valve lifters "1" and
the pads "2". Pads can only be selected in 0.05
mm increments.
• Place a rag in the timing chain
space to prevent pads from falling e. Locate the rounded-off value and
into the crankcase. the measured valve clearance in
• Identity each valve lifter and pad the chart "PAD SELECTION TA-
position very carefully so that they BLE". The field where these two
can be reinstalled in their original coordinates intersect shows the
place. new pad number to use.

Use the new pad number only as a

guide when verifying the valve clear-
ance adjustment.

f. Install the new pads "3" and the

valve lifters "4".

• Apply the engine oil on the valve lift-

ers.
• Apply the molybdenum disulfide oil
on the valve stem ends.
• Valve lifter must turn smoothly
when rotated with a finger.
• Be careful to reinstall valve lifters
and pads in their original place.

c. Select the proper pad using the

pad selecting table.
Pad Availabili-
Pad range ty: 25 incre-
ments
No. 1.20
Pads are avail-
120– mm–
able in 0.05 mm
No. 2.40
increments
240 mm

3-17
 ENGINE

INTAKE

MEASURED INSTALLED PAD NUMBER

CLEARANCE 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.00 - 0.04 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230
0.05 - 0.09 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235
0.10 - 0.15 STANDARD CLEARANCE
0.16 - 0.20 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.21 - 0.25 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.26 - 0.30 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.31 - 0.35 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.36 - 0.40 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.41 - 0.45 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.46 - 0.50 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.51 - 0.55 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.56 - 0.60 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.61 - 0.65 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.66 - 0.70 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.71 - 0.75 180 185 190 195 200 205 210 215 220 225 230 235 240
0.76 - 0.80 185 190 195 200 205 210 215 220 225 230 235 240
VALVE CLEARANCE (cold):
0.81 - 0.85 190 195 200 205 210 215 220 225 230 235 240
0.86 - 0.90 195 200 205 210 215 220 225 230 235 240
0.10 - 0.15 mm
0.91 - 0.95 200 205 210 215 220 225 230 235 240 Example: Installed is 175
0.96 - 1.00 205 210 215 220 225 230 235 240 Measured clearance is 0.23 mm
1.01 - 1.05 210 215 220 225 230 235 240 Replace 175 pad with 185 pad
1.06 - 1.10 215 220 225 230 235 240 Pad number: (example)
1.11 - 1.15 220 225 230 235 240 Pad No. 175 = 1.75 mm
1.16 - 1.20 225 230 235 240
Pad No. 185 = 1.85 mm
1.21 - 1.25 230 235 240
1.26 - 1.30 235 240
1.31 - 1.35 240
EXHAUST
MEASURED INSTALLED PAD NUMBER
CLEARANCE 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.00 - 0.04 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225
0.05 - 0.09 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230
0.10 - 0.16 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235
0.17 - 0.22 STANDARD CLEARANCE
0.23 - 0.25 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.26 - 0.30 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.31 - 0.35 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.36 - 0.40 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.41 - 0.45 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.46 - 0.50 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.51 - 0.55 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.56 - 0.60 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.61 - 0.65 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.66 - 0.70 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.71 - 0.75 175 180 185 190 195 200 205 210 215 220 225 230 235 240
0.76 - 0.80 180 185 190 195 200 205 210 215 220 225 230 235 240
0.81 - 0.85 185 190 195 200 205 210 215 220 225 230 235 240
0.86 - 0.90 190 195 200 205 210 215 220 225 230 235 240 VALVE CLEARANCE (cold):
0.91 - 0.95 195 200 205 210 215 220 225 230 235 240 0.17 - 0.22 mm
0.96 - 1.00 200 205 210 215 220 225 230 235 240 Example: Installed is 175
1.01 - 1.05 205 210 215 220 225 230 235 240
Measured clearance is 0.27 mm
1.06 - 1.10 210 215 220 225 230 235 240
1.11 - 1.15 215 220 225 230 235 240
Replace 175 pad with 185 pad
1.16 - 1.20 220 225 230 235 240 Pad number: (example)
1.21 - 1.25 225 230 235 240 Pad No. 175 = 1.75 mm
1.26 - 1.30 230 235 240 Pad No. 185 = 1.85 mm
1.31 - 1.35 235 240
1.36 - 1.40 240

3-18
 CHASSIS

CLEANING THE SPARK 6. Install:

ARRESTER (For USA) • Silencer cap
Silencer cap:
• Be sure the exhaust pipe and si- 5 Nm (0.5 m•kg, 3.6
lencer are cool before cleaning ft•lb)
the spark arrester.
• Do not start the engine when
First tighten the two screws "a" locat-
cleaning the exhaust system. A. Front
ed horizontally apart, and then tighten
1. Remove: the others. B. Rear
• Screw (silencer cap) "1" d. Place the other end of the tube
into a container.
e. Slowly apply the brake lever or
pedal several times.
f. Pull the lever in or push down on
the pedal. Hold the lever or pedal
in position.
g. Loosen the bleed screw and allow
the lever or pedal to travel to-
2. Remove:
CHASSIS wards its limit.
• Bolt (spark arrester) "1" BLEEDING THE HYDRAULIC h. Tighten the bleed screw when the
BRAKE SYSTEM lever or pedal limit has been
reached; then release the lever or
pedal.
Bleed the brake system if:
Bleed screw:
• The system has been disassem-
6 Nm (0.6 m•kg, 4.3
bled.
• A brake hose has been loosened ft•lb)
or removed. i. Repeat steps (e) to (h) until of the
• The brake fluid is very low. air bubbles have been removed
3. Remove:
• The brake operation is faulty. from the system.
• Tail pipe "1"
A dangerous loss of braking per-
• Gasket (tail pipe) "2"
formance may occur if the brake If bleeding is difficult, it may be nec-
• Spark arrester "3"
system is not properly bled. essary to let the brake fluid system
Pull the spark arrester out of the
silencer. 1. Remove: stabilize for a few hours. Repeat the
• Gasket (spark arrester) "4" • Brake master cylinder cap bleeding procedure when the tiny
• Diaphragm bubbles in the system have disap-
• Reservoir float (front brake) peared.
• Protector (rear brake) j. Add brake fluid to the level line on
2. Bleed: the reservoir.
• Brake fluid

Air bleeding steps: Check the operation of the brake

a. Add proper brake fluid to the res- after bleeding the brake system.
4. Clean:
ervoir.
• Spark arrester
b. Install the diaphragm. Be careful
Tap the spark arrester lightly, 3. Install:
not to spill any fluid or allow the
then use a wire brush to remove • Protector (rear brake)
reservoir to overflow.
any carbon deposits. • Reservoir float (front brake)
c. Connect the clear plastic tube "2"
5. Install: • Diaphragm
tightly to the caliper bleed screw
• Gasket (spark arrester) • Brake master cylinder cap
"1".
• Spark arrester
Insert the spark arrester into the
silencer and align the bolt holes.
• Gasket (tail pipe)
• Bolt (spark arrester)
Bolt (spark arrester):
7 Nm (0.7 m•kg, 5.1
ft•lb)

3-19
 CHASSIS

ADJUSTING THE FRONT BRAKE ADJUSTING THE REAR BRAKE CHECKING AND REPLACING THE
1. Check: 1. Check: FRONT BRAKE PADS
• Brake lever position "a" • Brake pedal height "a" 1. Inspect:
Out of specification → Adjust. • Brake pad thickness "a"
Brake lever position "a": Brake pedal height "a": Out of specification → Replace as
10 mm (0.39 in) a set.
Standard posi- Extent of ad- Brake pad thickness:
tion justment 4.4 mm (0.17 in)
76–97 mm <Limit>: 1.0 mm (0.04
95 mm (3.74 in)
(2.99–3.82 in) in)

2. Adjust:
• Brake pedal height

2. Remove: Pedal height adjustment steps: 2. Replace:

a. Loosen the locknut "1". • Brake pad
• Brake lever cover
3. Adjust: b. Turn the adjusting nut "2" until the
• Brake lever position pedal height "a" is within specified
height. Brake pad replacement steps:
c. Tighten the locknut. a. Remove the pad pin plug "1".
Brake lever position adjustment
steps:
a. Loosen the locknut "1". • Adjust the pedal height between
b. Turn the adjusting bolt "2" until the the maximum "A" and the mini-
lever position "a" is within speci- mum "B" as shown. (In this ad-
fied position. justment, the bolt "3" end "b"
should protrude out of the
threaded portion "4" but not be
less than 2 mm (0.08 in) "c" away b. Loosen the pad pin "2".
from the brake pedal "5"). c. Remove the brake caliper "3"
• After the pedal height adjust- from the front fork.
ment, make sure that the rear
brake does not drag.

c. Tighten the locknut.

Locknut:
5 Nm (0.5 m •kg, 3.6
ft•lb)
d. Remove the pad pin and brake
pads "4".
Be sure to tighten the locknut, as it
will cause poor brake perfor-
mance.

4. Install:
• Brake lever cover

3-20
 CHASSIS

e. Connect the transparent hose "5" j. Install the pad pin plug "10". c. Remove the rear wheel "4" and
to the bleed screw "6" and place Pad pin plug: brake caliper "5".
the suitable container under its 3 Nm (0.3 m•kg, 2.2 Refer to "FRONT WHEEL AND
end. ft•lb) REAR WHEEL" section in the
CHAPTER 6.

f. Loosen the bleed screw and push

the brake caliper piston in. d. Remove the pad pin "6" and brake
3. Inspect: pads "7".
• Brake fluid level
Do not reuse the drained brake flu-
Refer to "CHECKING THE
id.
BRAKE FLUID LEVEL" section.
g. Tighten the bleed screw. 4. Check:
• Brake lever operation
Bleed screw:
A softy or spongy feeling → Bleed
6 Nm (0.6 m•kg, 4.3
brake system.
ft•lb)
Refer to "BLEEDING THE HY-
h. Install the brake pads "7" and pad DRAULIC BRAKE SYSTEM" sec- e. Connect the transparent hose "8"
pin. tion. to the bleed screw "9" and place
the suitable container under its
CHECKING AND REPLACING THE
end.
• Install the brake pads with their pro- REAR BRAKE PADS
jections "a" into the brake caliper re- 1. Inspect:
cesses "b". • Brake pad thickness "a"
• Temporarily tighten the pad pin at Out of specification → Replace as
this point. a set.
Brake pad thickness:
6.4 mm (0.25 in)
<Limit>: 1.0 mm (0.04
in) f. Loosen the bleed screw and push
the brake caliper piston in.

Do not reuse the drained brake flu-

i. Install the brake caliper "8" and id.
tighten the pad pin "9". g. Tighten the bleed screw.
Bolt (brake caliper): Bleed screw:
23 Nm (2.3 m•kg, 17 6 Nm (0.6 m•kg, 4.3
ft•lb) 2. Replace: ft•lb)
Pad pin: • Brake pad
18 Nm (1.8 m•kg, 13 h. Install the brake pad "10" and pad
ft•lb) pin "11".
Brake pad replacement steps:
a. Remove the protector "1" and pad
pin plug "2". • Install the brake pads with their pro-
jections "a" into the brake caliper re-
cesses "b".
• Temporarily tighten the pad pin at
this point.

b. Loosen the pad pin "3".

3-21
 CHASSIS

i. Install the brake caliper "12" and CHECKING THE DRIVE CHAIN
rear wheel "13". 1. Measure:
Refer to "FRONT WHEEL AND • Drive chain length (15 links) "a"
REAR WHEEL" section in the Out of specification → Replace.
CHAPTER 6. Drive chain length (15
j. Tighten the pad pin "14". links):
Pad pin: <Limit>: 239.3 mm
18 Nm (1.8 m•kg, 13 (9.42 in)
ft•lb) CHECKING THE BRAKE FLUID
LEVEL
1. Place the brake master cylinder • While measuring the drive chain
so that its top is in a horizontal po- length, push down on the drive
sition. chain to increase its tension.
2. Inspect: • Measure the length between drive
• Brake fluid level chain roller "1" and "16" as shown.
Fluid at lower level → Fill up. • Perform this measurement at two or
Recommended brake flu- three different places.
id:
k. Install the pad pin plug "15" and
DOT #4
protector "16".
Pad pin plug:
3 Nm (0.3 m•kg, 2.2 • Use only designated quality
ft•lb) brake fluid to avoid poor brake
Bolt (protector): performance.
7 Nm (0.7 m•kg, 5.1 • Refill with same type and brand
ft•lb) of brake fluid; mixing fluids 2. Remove:
could result in poor brake perfor- • Drive chain "1"
mance.
• Be sure that water or other con- Remove the drive chain using a drive
taminants do not enter master chain cutter "2".
cylinder when refilling.
• Clean up spilled fluid immediate-
ly to avoid erosion of painted
surfaces or plastic parts.

3. Inspect:
• Brake fluid level
Refer to "CHECKING THE
BRAKE FLUID LEVEL" section.
3. Clean:
4. Check:
• Drive chain
• Brake pedal operation
Brush off as much dirt as possi-
A softy or spongy feeling → Bleed
ble. Then clean the drive chain
brake system. a. Lower level using the chain cleaner.
Refer to "BLEEDING THE HY- A. Front
DRAULIC BRAKE SYSTEM" sec- B. Rear
tion. CHECKING THE SPROCKET This machine has a drive chain
CHECKING THE REAR BRAKE 1. Inspect: with small rubber O-rings "1" be-
PAD INSULATOR • Sprocket teeth "a" tween the side plates. Steam
1. Remove: Excessive wear → Replace. cleaning, high-pressure washes,
• Brake pad certain solvent and kerosene can
Refer to "CHECKING AND RE- Replace the drive sprocket, rear damage these O-rings.
PLACING THE REAR BRAKE wheel sprocket and drive chain as a
PADS" section. set.
2. Inspect:
• Rear brake pad insulator "1"
Damage → Replace.

3-22
 CHASSIS

4. Inspect: b. Adjust the drive chain slack by

• O-ring "1" (drive chain) turning the adjusters "3".
Damage → Replace the drive To tighten→Turn the adjuster "3"
chain. counterclockwise.
• Roller "2" To loosen→Turn the adjuster "3"
• Side plate "3" clockwise and push wheel for-
Damage/wear → Replace the ward.
drive chain.
8. Lubricate: c. Turn each adjuster exactly the
• Drive chain same amount to maintain correct
axle alignment. (There are marks
Drive chain lubricant:
"a" on each side of the drive chain
SAE 10W-40 motor oil
puller alignment.) NOTICE: Im-
or suitable chain lubri-
proper drive chain slack will
cants
overload the engine as well as
other vital parts of the motorcy-
5. Check: cle and can lead to chain slip-
• Drive chain stiffness "a" page or breakage. To prevent
Clean and oil the drive chain and this from occurring, keep the
hold as illustrated. drive chain slack within the
Stiff → Replace the drive chain. specified limits.

ADJUSTING THE DRIVE CHAIN

SLACK
1. Elevate the rear wheel by placing
the suitable stand under the en-
gine.
2. Check:
6. Install: • Drive chain slack "a"
• Chain joint "1" Above the seal guard installation Turn the adjuster so that the drive
• O-ring "2" bolt. chain is in line with the sprocket, as
• Drive chain "3" Out of specification → Adjust. viewed from the rear.
• Link plate "4" Drive chain slack:
d. Tighten the axle nut while pushing
48–58 mm (1.9–2.3 in)
down the drive chain.
When installing the drive chain, apply
the lithium soap base grease on the Axle nut:
chain joint and O-rings. Before checking and/or adjusting, ro- 125 Nm (12.5 m•kg, 90
tate the rear wheel through several ft•lb)
revolutions and check the slack sev- e. Tighten the locknuts.
eral times to find the tightest point.
Check and/or adjust the drive chain Locknut:
slack with the rear wheel in this "tight 19 Nm (1.9 m•kg, 13
chain" position. ft•lb)

CHECKING THE FRONT FORK

7. Install: 1. Inspect:
• Link plate • Front fork smooth action
Operate the front brake and
• Press the link plate onto the chain stroke the front fork.
joint using a drive chain riveter "5". Unsmooth action/oil leakage →
• Rivet the end of the chain joint us- Repair or replace.
ing a drive chain riveter. 3. Adjust:
• After riveting the chain joint, make • Drive chain slack
sure its movement is smooth.
Drive chain slack adjustment
steps:
a. Loosen the axle nut "1" and lock-
nuts "2".

3-23
 CHASSIS

CLEANING THE FRONT FORK OIL ADJUSTING THE FRONT FORK

SEAL AND DUST SEAL REBOUND DAMPING FORCE Extent of adjustment:
1. Remove: 1. Adjust:
• Protector • Rebound damping force Maximum Minimum
• Dust seal "1" By turning the adjuster "1". 20 clicks out
Fully turned in
Stiffer "a" → Increase the re- (from maximum
Use a thin screw driver, and be care- position
bound damping force. (Turn position)
ful not to damage the inner fork tube the adjuster "1" in.)
and dust seal. Softer "b" → Decrease the re-
bound damping force. (Turn
the adjuster "1" out.)

Extent of adjustment:

Maximum Minimum
20 clicks out • STANDARD POSITION:
Fully turned in This is the position which is back
(from maximum
2. Clean: position by the specific number of clicks
position)
• Dust seal "a" from the fully turned-in position.
• Oil seal "b" Standard position:
10 clicks out
• Clean the dust seal and oil seal af- * 11 clicks out
ter every run. * Except for USA and CDN
• Apply the lithium soap base grease
on the inner tube.
Do not force the adjuster past the
• STANDARD POSITION: minimum or maximum extent of
This is the position which is back adjustment. The adjuster may be
by the specific number of clicks damaged.
from the fully turned-in position.
Standard position:
9 clicks out Always adjust each front fork to
the same setting. Uneven adjust-
RELIEVING THE FRONT FORK ment can cause poor handling and
INTERNAL PRESSURE loss of stability.
Do not force the adjuster past the
If the front fork initial movement feels minimum or maximum extent of 3. Install:
stiff during a run, relieve the front fork adjustment. The adjuster may be • Rubber cap
internal pressure. damaged. CHECKING THE REAR SHOCK
ABSORBER
1. Elevate the front wheel by placing 1. Inspect:
a suitable stand under the engine. Always adjust each front fork to • Swingarm smooth action
2. Remove the air bleed screw "1" the same setting. Uneven adjust- Abnormal noise/unsmooth action
and release the internal pressure ment can cause poor handling and → Grease the pivoting points or
from the front fork. loss of stability. repair the pivoting points.
3. Install: Damage/oil leakage → Replace.
• Air bleed screw ADJUSTING THE FRONT FORK
Air bleed screw: COMPRESSION DAMPING FORCE
1 Nm (0.1 m•kg, 0.7 1. Remove:
ft•lb) • Rubber cap
2. Adjust:
• Compression damping force
By turning the adjuster "1".
Stiffer "a" → Increase the com-
pression damping force. (Turn
the adjuster "1" in.)
Softer "b" → Decrease the com-
pression damping force. (Turn
the adjuster "1" out.)

3-24
 CHASSIS

ADJUSTING THE REAR SHOCK

ABSORBER SPRING PRELOAD Extent of adjustment:
1. Elevate the rear wheel by placing
the suitable stand under the en- Maximum Minimum
gine. 20 clicks out
2. Remove: Fully turned in
(from maximum
• Rear frame position
position)
3. Measure:
• Spring fitting length
Extent of adjustment:
Standard fitting length:
Maximum Minimum
I.D. MARK/Q'TY Length Position in Position in
Yellow/1 249 mm which the which the
(9.80 in) spring is turned spring is turned
* 245.0 mm in 22 mm (0.87 in 1.5 mm (0.06
• STANDARD POSITION:
(9.65 in) in) from its free in) from its free
This is the position which is back
** 248.5 mm length. length.
by the specific number of clicks
(9.78 in) from the fully turned-in position.
* For AUS, NZ and ZA • Be sure to remove all dirt and mud (Which align the punch mark "a"
** For EUROPE from around the locknut and adjust- on the adjuster with the punch
er before adjustment. mark "b" on the bracket.)
• The length of the spring (installed) Standard position:
The I.D. mark "a" is marked at the end changes 1.5 mm (0.06 in) per turn 10–13 clicks out
of the spring. of the adjuster.

Do not force the adjuster past the

Never attempt to turn the adjuster
minimum or maximum extent of
beyond the maximum or minimum
adjustment. The adjuster may be
setting.
damaged.
e. Tighten the locknut.
Locknut:
30 Nm (3.0 m•kg, 22
ft•lb)

5. Install:
• Rear frame (upper)
Rear frame (upper): ADJUSTING THE REAR SHOCK
38 Nm (3.8 m•kg, 27 ABSORBER LOW COMPRESSION
4. Adjust: ft•lb) DAMPING FORCE
• Spring preload 1. Adjust:
• Rear frame (lower) • Low compression damping force
Rear frame (lower): By turning the adjuster "1".
Adjustment steps: 32 Nm (3.2 m•kg, 23
a. Loosen the locknut "1". Stiffer "a" → Increase the low
ft•lb) compression damping force.
b. Loosen the adjuster "2" until there
is some clearance between the ADJUSTING THE REAR SHOCK (Turn the adjuster "1" in.)
spring and adjuster. ABSORBER REBOUND DAMPING Softer "b" → Decrease the low
c. Measure the spring free length FORCE compression damping force.
"a". 1. Adjust: (Turn the adjuster "1" out.)
d. Turn the adjuster "2". • Rebound damping force
By turning the adjuster "1". Extent of adjustment:
Stiffer → Increase the spring pre-
load. (Turn the adjuster "2" in.) Stiffer "a" → Increase the re-
Softer → Decrease the spring pre- bound damping force. (Turn Maximum Minimum
load. (Turn the adjuster "2" the adjuster "1" in.) 20 clicks out
Softer "b" → Decrease the re- Fully turned in
out.) (from maximum
bound damping force. (Turn position
position)
the adjuster "1" out.)

3-25
 CHASSIS

CHECKING AND TIGHTENING THE

SPOKES
The following procedure applies to all
of the spokes.
1. Check:
• Spokes
Bend/damage → Replace.
Loose spoke → Retighten.
• STANDARD POSITION: • STANDARD POSITION: Tap the spokes with a screw-
This is the position which is back This is the position which is back driver.
by the specific number of clicks by the specific number of turns
from the fully turned-in position. from the fully turned-in position.
(Which align the punch mark "a" (Which align the punch mark "a"
on the adjuster with the punch on the adjuster with the punch
mark "b" on the high compression mark "b" on the adjuster body.)
damping adjuster.) Standard position:
Standard position: 1–1-1/3 turns out
11–14 clicks out * 1-1/12–1-5/12 turns
* 12–15 clicks out out
A tight spoke will emit a clear, ringing
* For AUS, NZ and ZA * For EUROPE
tone; a loose spoke will sound flat.

2. Tighten:
Do not force the adjuster past the Do not force the adjuster past the • Spokes
minimum or maximum extent of minimum or maximum extent of (with a spoke nipple wrench "1")
adjustment. The adjuster may be adjustment. The adjuster may be
damaged. damaged. Be sure to retighten these spokes be-
fore and after break-in.

ADJUSTING THE REAR SHOCK CHECKING THE TIRE PRESSURE

ABSORBER HIGH COMPRESSION 1. Measure: Spoke nipple wrench:
DAMPING FORCE • Tire pressure YM-01521/90890-01521
1. Adjust: Out of specification → Adjust.
• High compression damping force Standard tire pressure: Spokes:
By turning the adjuster "1". 100 kPa (1.0 kgf/cm2, 3 Nm (0.3 m•kg, 2.2
Stiffer "a" → Increase the high 15 psi) ft•lb)
compression damping force. CHECKING THE WHEELS
(Turn the adjuster "1" in.) 1. Inspect:
Softer "b" → Decrease the high • Check the tire while it is cold. • Wheel runout
compression damping force. • Loose bead stoppers allow the tire to Elevate the wheel and turn it.
(Turn the adjuster "1" out.) slip off its position on the rim when Abnormal runout → Replace.
the tire pressure is low.
• A tilted tire valve stem indicates that
Extent of adjustment:
the tire slips off its position on the rim.
• If the tire valve stem is found tilted,
Maximum Minimum the tire is considered to be slipping off
2 turns out its position. Correct the tire position.
Fully turned in
(from maximum
position
position)

3-26
 CHASSIS

2. Inspect: • Install the handlebar so that the pro-

• Bearing free play jection "c" of the handlebar upper
Exist play → Replace. holder is positioned at the mark on
the handlebar as shown.
• Insert the end of the fuel breather
hose "13" into the hole in the steer-
ing stem.

d. Tighten the steering ring nut "3"

using steering nut wrench "4". First tighten the bolts on the front
side of the handlebar upper holder,
CHECKING AND ADJUSTING THE • Apply the lithium soap base grease and then tighten the bolts on the
STEERING HEAD on the thread of the steering stem. rear side.
1. Place a stand under the engine to • Set the torque wrench to the steer-
raise the front wheel off the ing nut wrench so that they form a Steering stem nut:
ground. WARNING! Securely right angle. 145 Nm (14.5 m•kg, 105
support the vehicle so that
ft•lb)
there is no danger of it falling Steering nut wrench: Handlebar upper holder:
over. YU-33975/90890-01403 28 Nm (2.8 m•kg, 20
2. Check:
ft•lb)
• Steering stem Steering ring nut (initial Pinch bolt (upper brack-
Grasp the bottom of the forks and tightening): et):
gently rock the fork assembly 38 Nm (3.8 m•kg, 27 21 Nm (2.1 m•kg, 15
back and forth. ft•lb) ft•lb)
Free play → Adjust steering head.
Headlight:
7 Nm (0.7 m•kg, 5.1
ft•lb)

3. Check: e. Loosen the steering ring nut one

• Steering smooth action turn.
Turn the handlebar lock to lock. f. Retighten the steering ring nut us-
ing the steering nut wrench.
Unsmooth action → Adjust steer-
ing ring nut.
Avoid over-tightening.

Steering ring nut (final

tightening):
7 Nm (0.7 m•kg, 5.1
ft•lb)
g. Check the steering stem by turn-
4. Adjust: ing it lock to lock. If there is any
• Steering ring nut binding, remove the steering stem
assembly and inspect the steer-
ing bearings.
Steering ring nut adjustment h. Install the washer "5", collar "6",
steps: upper bracket "7", washer "8",
a. Remove the headlight. steering stem nut "9", handlebar
b. Remove the handlebar and upper "10", handlebar upper holder "11"
bracket. and headlight "12".
c. Loosen the steering ring nut "1"
using the steering nut wrench "2". • Install the collar "6" with the larger
Steering nut wrench: inside diameter facing downward.
YU-33975/90890-01403 • The handlebar upper holder should
be installed with the punched mark
"a" forward.
• Install the handlebar so that the
marks "b" are in place on both
sides.

3-27
 CHASSIS

LUBRICATION

To ensure smooth operation of all A. Use Yamaha cable lube or

components, lubricate your machine equivalent on these areas.
during setup, after break-in, and after B. Use SAE 10W-40 motor oil or
every ride. suitable chain lubricants.
1. All control cable C. Lubricate the following areas
2. Clutch lever pivot with high quality, lightweight lith-
3. Shift pedal pivot ium-soap base grease.
4. Footrest pivot
5. Throttle-to-handlebar contact
6. Drive chain Wipe off any excess grease, and
7. Tube guide cable winding por- avoid getting grease on the brake
tion discs.
8. Throttle cable end
9. Clutch cable end
10. Hot starter cable end

3-28
 ELECTRICAL

ELECTRICAL CHECKING THE IGNITION TIMING CHECKING AND CHARGING THE

CHECKING THE SPARK PLUG 1. Remove: BATTERY
1. Remove: • Timing mark accessing screw "1"
• Spark plug Batteries generate explosive hy-
2. Inspect: drogen gas and contain electrolyte
• Electrode "1" which is made of poisonous and
Wear/damage → Replace. highly caustic sulfuric acid. There-
• Insulator color "2" fore, always follow these preven-
Normal condition is a medium to tive measures:
light tan color. • Wear protective eye gear when
Distinctly different color → Check handling or working near batter-
the engine condition. 2. Attach:
• Timing light ies.
• Digital tachometer • Charge batteries in a well-venti-
When the engine runs for many hours lated area.
To the ignition coil lead (orange
at low speeds, the spark plug insula- • Keep batteries away from fire,
lead"1").
tor will become sooty, even if the en- sparks or open flames (e.g.,
gine and carburetor are in good Timing light: welding equipment, lighted ciga-
operating condition. YM-33277-A/90890- rettes).
03141 • DO NOT SMOKE when charging
3. Measure:
or handling batteries.
• Plug gap "a"
• KEEP BATTERIES AND ELEC-
Use a wire gauge or thickness
TROLYTE OUT OF REACH OF
gauge.
CHILDREN.
Out of specification → Regap.
• Avoid bodily contact with elec-
Spark plug gap: trolyte as it can cause severe
0.7–0.8 mm (0.028– burns or permanent eye injury.
0.031 in) FIRST AID IN CASE OF BODILY
3. Adjust: CONTACT:
• Engine idling speed EXTERNAL
Refer to "ADJUSTING THE EN- • Skin — Wash with water.
GINE IDLING SPEED" section. • Eyes — Flush with water for 15
4. Check: minutes and get immediate med-
• Ignition timing ical attention.
Visually check the stationary INTERNAL
pointer "a" is within the firing • Drink large quantities of water or
range "b" on the rotor. milk followed with milk of magne-
4. Clean the plug with a spark plug
Incorrect firing range → Check ro- sia, beaten egg or vegetable oil.
cleaner if necessary.
tor and pickup assembly. Get immediate medical attention.
5. Tighten:
• Spark plug
Spark plug:
Charging time, charging amperage
13 Nm (1.3 m•kg, 9.4
and charging voltage for an MF
ft•lb)
battery are different from those of
conventional batteries. The MF
• Before installing a spark plug, clean battery should be charged as ex-
the gasket surface and plug sur- plained in the charging method il-
face. 5. Install: lustrations. If the battery is
• Finger-tighten "a" the spark plug • Timing mark accessing screw overcharged, the electrolyte level
before torquing to specification "b". will drop considerably. Therefore,
take special care when charging
the battery.

Since MF batteries are sealed, it is

not possible to check the charge state
of the battery by measuring the spe-
cific gravity of the electrolyte. There-
fore, the charge of the battery has to
be checked by measuring the voltage
at the battery terminals.

3-29
 ELECTRICAL

1. Remove:
• Seat
2. Disconnect: • Never remove the MF battery
• Battery leads sealing caps.
(from the battery terminals) • Do not use a high-rate battery
charger since it forces a high-
amperage current into the bat-
First, disconnect the negative bat- tery quickly and can cause bat-
tery lead "1", and then the positive tery overheating and battery
battery lead "2". plate damage.
• If it is impossible to regulate the
charging current on the battery
charger, be careful not to over-
charge the battery.
• When charging a battery, be sure
to remove it from the machine. (If
charging has to be done with the
battery mounted on the machine,
disconnect the negative battery
3. Remove: lead from the battery terminal.)
• Battery band • To reduce the chance of sparks,
• Battery do not plug in the battery charger
4. Measure: until the battery charger leads
• Battery charge are connected to the battery.
A. Relationship between the • Before removing the battery
Measurement steps: open-circuit voltage and the charger lead clips from the bat-
a. Connect a pocket tester "1" to the charging time at 20 °C (68 °F) tery terminals, be sure to turn off
battery terminals. (These values vary with the the battery charger.
temperature, the condition of • Make sure the battery charger
the battery plates, and the lead clips are in full contact with
electrolyte level.) the battery terminal and that they
B. Open-circuit voltage are not shorted. A corroded bat-
C. Charging time (hours) tery charger lead clip may gener-
D. Time (minutes) ate heat in the contact area and a
E. Charging condition of the bat- weak clip spring may cause
tery sparks.
Tester positive probe → battery F. Ambient temperature 20 °C • If the battery becomes hot to the
positive terminal (68 °F) touch at any time during the
Tester negative probe → battery a. Charging charging process, disconnect
negative terminal b. Check the open-circuit volt- the battery charger and let the
age battery cool before reconnecting
5. Charge: it. Hot batteries can explode!
• The charge state of an MF battery • As shown in the following illus-
• Battery
can be checked by measuring its tration, the open-circuit voltage
(refer to the appropriate charging
open-circuit voltage (i.e., the volt- of an MF battery stabilizes about
method illustration)
age when the positive terminal is 30 minutes after charging has
disconnected). been completed. Therefore, wait
• No charging is necessary when the Do not quick charge a battery. 30 minutes after charging is com-
opencircuit voltage equals or ex- pleted before measuring the
ceeds 12.8 V. open-circuit voltage.
b. Check the charge of the battery,
as shown in the charts and the fol-
lowing example.
Example
Open-circuit voltage = 12.0 V
Charging time = 6.5 hours
Charge of the battery = 20–30%

3-30
 ELECTRICAL

Charging method using a variable voltage charger

3-31
 ELECTRICAL

Charging method using a constant voltage charger

3-32
 ELECTRICAL

6. Install: REPLACING THE HEADLIGHT

• Battery BULBS
• Battery band 1. Remove:
7. Connect: • Headlight
• Battery leads Refer to "REMOVING THE SEAT,
(to the battery terminals) FUEL TANK AND SIDE COV-
ERS" section.
2. Remove:
First, connect the positive lead "1", 2. Reserve fuse • Headlight bulb holder cover "1"
then the negative lead "2". c. If the pocket tester indicates " ∞ ",
replace the fuse.

3. Replace:
• Blown fuse

Replacement steps:
a. Set the main switch to "OFF". 3. Remove:
b. Install a new fuse of the correct • Headlight bulb holder "1"
8. Check: amperage.
• Battery terminals c. Set on the switches to verify if the
Dirt → Clean with a wire brush. Remove the headlight bulb holder by
electrical circuit is operational.
Loose connection → Connect pushing it in and turning it counter-
d. If the fuse immediately blows
properly. clockwise.
again, check the electrical circuit.
9. Lubricate:
• Battery terminal Items Amperage Q'ty
rating
Recommended lubricant:
Lithium soap base Main fuse 10 A 1
grease
10. Install: Never use a fuse with an amperage
• Seat rating other than that specified. Im-
CHECKING THE FUSE provising or using a fuse with the 4. Remove:
wrong amperage rating may cause • Headlight bulb
extensive damage to the electrical
To avoid a short circuit, always set
system, cause the starting and ig-
the main switch to "OFF" when
nition systems to malfunction and Since the headlight bulb gets ex-
checking or replacing a fuse.
could possibly cause a fire. tremely hot, keep flammable prod-
1. Remove: ucts and your hands away from the
• Seat bulb unit it has cooled down.
• Fuse cover
5. Install:
2. Check:
• Headlight bulb
• Continuity

Checking steps: Avoid touching the glass part of

a. Remove the fuse "1". the headlight bulb to keep it free
b. Connect the pocket tester to the form oil, otherwise the transparen-
fuse and check the continuity. cy of the glass, the life of the bulb
4. Install: and the luminous flux will be ad-
• Fuse cover versely affected. If the headlight
Set the pocket tester selector to " Ω× • Seat bulb gets soiled, thoroughly clean
1".
it with a cloth moistened with alco-
hol or lacquer thinner.
Pocket tester:
YU-3112-C/90890-
03112

3-33
 ELECTRICAL

6. Install:
• Headlight bulb holder
7. Install:
• Headlight bulb holder cover
8. Install:
• Headlight
Headlight:
7 Nm (0.7 m•kg, 5.1
ft•lb)
Refer to "REMOVING THE SEAT,
FUEL TANK AND SIDE COV-
ERS" section.
ADJUSTING THE HEADLIGHT
BEAMS
1. Adjust:
• Headlight beam (vertically)

Adjusting steps:
a. Turn the adjusting screw "1" in di-
rection "a" or "b".
Direction "a" Headlight beam is
raised.
Direction "b" Headlight beam is
lowered.

3-34
 ENGINE (Except for Canada)

TUNING • After installing the carburetor, CONSTRUCTION OF

check that the throttle operates CARBURETOR AND SETTING
ENGINE (Except for Canada) correctly and opens and closes PARTS
CARBURETOR SETTING smoothly. The FLATCR carburetor has a prima-
• The air/fuel mixture will vary de- ry main jet. This type of main jet is
pending on atmospheric conditions. ATMOSPHERIC CONDITIONS AND perfect for racing machines since it
Therefore, it is necessary to take CARBURETOR SETTINGS supplies an even flow of fuel, even at
into consideration the air pressure, full load. Use the main jet and the jet
ambient temperature, humidity, Air
needle to set the carburetor.
etc., when adjusting the carburetor. Air Hu- pres-
Mix- Set-
• Perform a test run to check for prop- tem midi- sure
ture ting
er engine performance (e.g., throt- p. ty (alti-
tle response) and spark plug(-s) tude)
discoloration or fouling. Use these Low Rich- Lean-
High High
readings to determine the best pos- (high) er er
sible carburetor setting. High Lean- Rich-
Low Low
(low) er er
It is recommended to keep a record of
all carburetor settings and external
conditions (e.g., atmospheric condi- The air density (i.e., concentration of
tions, track/surface conditions, lap oxygen in the air) determines the rich-
times) to make future carburetor set- ness or leanness of the air/fuel mix-
ting easier. ture.
• Higher temperature expands the air
with its resultant reduced density.
• Higher humidity reduces the
• The carburetor is a part of the 1. Jet needle
amount of oxygen in the air by so
fuel line. Therefore, be sure to in- 2. Pilot air jet
much of the water vapor in the
stall it in a wellventilated area, 3. Needle jet
same air.
away from flammable objects 4. Main jet
• Lower atmospheric pressure (at a
and any sources of fire. 5. Pilot jet
high altitude) reduces the density of
• Never look into the carburetor in- ADJUSTING THE MAIN JET
the air.
take. Flames may shoot out from The richness of the air-fuel mixture at
the pipe if the engine backfires EFFECT OF SETTING PARTS IN full throttle can be set by changing the
while it is being started. Gasoline RELATION TO THROTTLE VALVE main jet "1".
may be discharged from the ac- OPENING #170
celerator pump nozzle when the Standard main jet
* #160
carburetor has been removed.
* For EUROPE
If the air-fuel mixture is too rich or too
• The carburetor is extremely sen- lean, the engine power will drop, re-
sitive to foreign matter (dirt, sulting in poor acceleration.
sand, water, etc.). During instal-
lation, do not allow foreign mat-
ter to get into the carburetor.
• Always handle the carburetor
and its components carefully.
Even slight scratches, bends or
damage to carburetor parts may
prevent the carburetor from
functioning correctly. Carefully Effects of changing the main jet
perform all servicing with the ap- (reference)
propriate tools and without ap- A. Closed
plying excessive force. B. Fully open
• When the engine is stopped or 1. Pilot jet
when riding at no load, do not 2. Throttle valve cutaway
open and close the throttle un- 3. Jet needle A. Idle
necessarily. Otherwise, too 4. Main jet B. Fully open
much fuel may be discharged, 1. #180
starting may become difficult or 2. #160
the engine may not run well. 3. #170

4-1
 ENGINE (Except for Canada)

ADJUSTING THE PILOT JET Effects of changing the jet needle ADJUSTING THE LEAK JET
The richness of the air-fuel mixture groove position (reference) (ADJUSTING THE ACCELERATOR
with the throttle open 1/4 or less can PUMP)
be set by adjusting the pilot jet "1". The leak jet "1" is a setting part that
#42 adjusts the flow of fuel discharged by
Standard pilot jet the accelerator pump. Since the ac-
* #45
A. Idle celerator pump operates only when
* For EUROPE B. Fully open throttle is open, the leak jet is used to
1. No.5 groove adjust a fuel mixture ratio for quick
2. No.3 groove throttle opening and is therefore dif-
3. No.4 groove ferent from other setting parts that ad-
ADJUSTING THE JET NEEDLE just a fuel mixture for each throttle
The jet needle is adjusted by chang- opening (each engine speed).
ing it. 1. When the engine breathes hard in
quick throttle opening, select a
GDEPR leak jet having lower calibrating
Supplied jet needle
* GDEMS No. than standard to enrich the
Effects of adjusting the pilot jet
(reference) * For EUROPE mixture. <Example> #70 → #65
2. When rough engine operation is
The jet needle setting parts, having
felt in quick throttle opening, se-
the same taper angle, are available in
lect a leak jet having higher cali-
different straight portion diameters.
brating No. than standard to lean
a. Diameter of the straight por-
out the mixture. <Example> #70
A. Idle tion
→ #85
B. Fully open

4
1. #45 Standard leak jet #70
2. #40
3. #42
ADJUSTING THE JET NEEDLE
GROOVE POSITION
Adjusting the jet needle "1" position
affects the acceleration when the
throttle is 1/8 to 3/4 open. Effects of changing the jet needle
1. Too rich at intermediate speeds (reference)
• Rough engine operation is felt (Diameter of the straight portion)
and the engine will not pick up Changing the diameter of the straight
speed smoothly. portion adjusts the air-fuel mixture
Step up the jet needle clip by one when the throttle is 1/8 to 1/4 open.
groove and move down the nee-
dle to lean out the mixture.
2. Too lean at intermediate speeds
• The engine breathes hard and will
not pick up speed quickly. A. Idle
Step down the jet needle clip by B. Fully open
one groove and move up the nee- RELATIONSHIP WITH THROTTLE
dle to enrich the mixture. OPENING
Standard clip posi- No.4 The flow of the fuel through the car-
tion groove buretor main system is controlled by
the main jet and then, it is further reg-
ulated by the area between the main
nozzle and the jet needle.
The fuel flow relates to the diameter
of the straight portion of the jet needle
with the throttle 1/8 to 1/4 open and
relates to the clip position with the
throttle 1/8 to 3/4 open.
Therefore, the fuel flow is balanced at
each stage of throttle opening by the
combination of the jet needle straight
portion diameter and clip position.

4-2
 ENGINE (Except for Canada)

CARBURETOR SETTING PARTS Part

Leak jet Size number
Part
(-1494F-)
Main jet Size number
(-14943-) Rich #60 4JT-11
Rich #182 4MX-94 (STD) #70 4JT-15
#180 4MX-43 #80 4JT-19
#178 4MX-93 #90 4JT-23
#175 4MX-42 #100 4JT-27
#172 4MX-92 #110 4JT-29
(STD) #170 4MX-41 Lean #120 4JT-31
#168 4MX-91 * For EUROPE
#165 4MX-40
#162 4MX-90
* (STD) #160 4MX-39
Lean #158 4MX-89
Part
Pilot jet Size number
(-14948-)
Rich #50 4MX-07
#48 4MX-06
* (STD) #45 4MX-05
(STD) #42 4MX-04
Lean #40 4MX-03
Part
Jet needle Size number
(-14916-)
Rich GDEPN 5UM-BN
GDEPP 5UM-BP
GDEPQ 5UM-B1
GDEPR 5UM-BR
GDEPS 5UM-BS
GDEPT 5UM-BT
Lean GDEPU 5UM-BU
Rich GDEMP 5UM-VP
GDEMQ 5UM-V1
GDEMR 5UM-VR
GDEMS 5UM-VS
GDEMT 5UM-VT
GDEMU 5UM-VU
Lean GDEMV 5UM-VV

4-3
 ENGINE (Except for Canada)

EXAMPLES OF CARBURETOR SETTING DEPENDING ON SYMPTOM

Symptom Setting Checking

At full throttle Increase main jet calibration no. (Gradual- Discoloration of spark plug → If tan color, it
Hard breathing ly) is in good condition.
Shearing noise If cannot be corrected:
Whitish spark plug Clogged float valve seat
↓ Clogged fuel hose
Lean mixture Clogged fuel cock
Check that the accelerator pump operates
smoothly.
At full throttle Decrease main jet calibration no. (Gradual- Discoloration of spark plug → If tan color, it
Speed pick-up stops ly) is in good condition.
Slow speed pick-up If cannot be corrected:
Slow response Clogged air filter
Sooty spark plug Fuel overflow from carburetor
↓
Rich mixture
Lean mixture Lower jet needle clip position. (1 groove
Groove 1
down) Groove 2
Clip
Groove 3
Groove 4 Leaner
Rich mixture Raise jet needle clip position. (1 groove up) Groove 5
Groove 6
1/4–3/4 throttle Lower jet needle clip position. (1 groove Groove 7
(Standard)
Hard breathing down)
Lack of speed
Jet needle
Richer
1/4–1/2 throttle Raise jet needle clip position. (1 groove up)
Slow speed pick-up
Poor acceleration The clip position is the jet needle groove on
which the clip is installed.
The positions are numbered from the top.
Check that the accelerator pump operates
smoothly. (except for rich mixture symp-
tom).
Closed to 1/4 throttle Use jet needle with a smaller diameter. Slow-speed-circuit passage
Hard breathing Clogged → Clean.
Speed down Overflow from carburetor
Closed to 1/4 throttle Use jet needle with a larger diameter.
Poor acceleration Raise jet needle clip position. (1 groove up)
Poor response in the low to in- Raise jet needle clip position.
termediate speeds If this has no effect, lower the jet needle clip
position.
Poor response when throttle is Check overall settings. Check air filter for fouling.
opened quickly Use main jet with a lower calibration no. Check that the accelerator pump operates
Raise jet needle clip position. (1 groove up) smoothly.
If these have no effect, use a main jet with
a higher calibration no. and lower the jet
needle clip position.

This should be taken simply for an example. It is necessary to set the carburetor while checking the operating conditions
of the engine.

4-4
 CHASSIS

CHASSIS DRIVE AND REAR WHEEL • Under a stony or hard road condi-
SELECTION OF THE SECONDARY SPROCKETS SETTING PARTS tion, the tire pressure should be
REDUCTION RATIO (SPROCKET) higher to prevent a flat tire.
Part
Size Part number Extent of adjustment:
Secondary reduction ratio = name
100–120 kPa (1.0–1.2
Number of rear wheel sprocket Drive kgf/cm2, 15–18 psi)
teeth/Number of drive sprocket sprocket
teeth "1" FRONT FORK SETTING
The front fork setting should be made
50/13 (STD) 13T 9383B-13218
depending on the rider's feeling of an
Standard secondary (3.846) ** (STD) * 14T 9383B-14222 actual run and the circuit conditions.
reduction ratio * 47/14 The front fork setting includes the fol-
Rear
(3.357) lowing three factors:
wheel
* For EUROPE sprocket 1. Setting of air spring characteris-
"2" tics
<Requirement for selection of sec-
• Change the fork oil level.
ondary gear reduction ratio> ** (STD) ** 47T 1C3-25447-00 2. Setting of spring preload
• It is generally said that the second-
48T 5GS-25448-50 • Change the spring.
ary gear ratio should be reduced for
* 48T 1C3-25448-00 • Install the adjustment washer.
a longer straight portion of a speed
3. Setting of damping force
course and should be increased for * 49T 1C3-25449-00 • Change the compression damp-
a course with many corners. Actual-
(STD) 50T 5TJ-25450-80 ing.
ly, however, as the speed depends
• Change the rebound damping.
on the ground condition of the day * (STD) * 50T 1C3-25450-00
The spring acts on the load and
of the ride, be sure to run through * 51T 1C3-25451-00 the damping force acts on the
the circuit to set the machine suit-
52T 5TJ-25452-80 cushion travel speed.
able for the entire course.
• In actuality, it is very difficult to * 52T 1C3-25452-00 CHANGE IN LEVEL AND
achieve settings suitable for the en- CHARACTERISTICS OF FORK OIL
* For AUS and NZ Damping characteristic near the final
tire course and some settings may ** For EUROPE
be sacrificed. Thus, the settings stroke can be changed by changing
should be matched to the portion of the fork oil amount.
the course that has the greatest ef-
fect on the ride result. In such a Adjust the oil level in 5 mm (0.2 in)
case, run through the entire course increments or decrements. Too
while making notes of lap times to low oil level causes the front fork
find the best balance; then, deter- to produce a noise at full rebound
mine the secondary reduction ratio. or the rider to feel some pressure
• If a course has a long straight por- on his hands or body. Alternative-
tion where a machine can run at ly, too high oil level will develop
maximum speed, the machine is unexpectedly early oil lock with
generally set such that it can devel- the consequent shorter front fork
op its maximum revolutions toward travel and deteriorated perfor-
the end of the straight line, with care mance and characteristics. There-
taken to avoid the engine over-rev- fore, adjust the front fork within
ving. the specified range.
TIRE PRESSURE
Riding technique varies from rider to Tire pressure should be adjust to suit Standard oil level:
rider and the performance of a ma- the road surface condition of the cir- 132 mm (5.20 in)
chine also vary from machine to ma- cuit. Extent of adjustment:
chine. Therefore, do not imitate other 95–150 mm (3.74–5.91
Standard tire pressure:
rider's settings from the beginning but
100 kPa (1.0 kgf/cm2, in)
choose your own setting according to From top of outer tube
15 psi)
the level of your riding technique. with inner tube and
• Under a rainy, muddy, sandy, or damper rod fully com-
slippery condition, the tire pressure pressed without
should be lower for a larger area of spring.
contact with the road surface.
Extent of adjustment:
60–80 kPa (0.6–0.8 kgf/
cm2, 9.0–12 psi)

4-5
 CHASSIS

• Front fork spring "2"

SPRING
SPRI I.D.
PART
TYPE NG MARK
NUMBER
RATE (slits)
(-23141-)
0.408 5TJ-00 |
0.418 5TJ-10 ||
A. Load SOFT
0.428 5TJ-20 |||
B. Fork stroke
1. Without adjustment washer 0.438 5TJ-30 ||||
(standard) STD 0.449 5TJ-A0 —
2. 1 adjustment washer
0.459 5TJ-50 |-|
3. 2 adjustment washers STIFF
SETTING OF SPRING AFTER 0.469 5TJ-60 |-||
A. Air spring characteristics in REPLACEMENT
relation to oil level change As the front fork setting can be easily
The I.D. mark (slits) "a" is proved on
B. Load affected by rear suspension, take
the end of the spring.
C. Stroke care so that the machine front and
1. Max. oil level rear are balanced (in position, etc.)
2. Standard oil level when setting the front fork.
1. Use of soft spring When using a spring with a spring
3. Min. oil level
• Change the rebound damping. rate of 0.469 kg/mm, do not install
ADJUSTING THE SPRING two or more adjustment washers
Turn out one or two clicks.
PRELOAD for each front fork.
• Change the compression damp-
The spring preload is adjusted by in-
ing.
stalling the adjustment washer "1" be-
Turn in one or two clicks.
tween the fork spring "2" and damper
rod "3".
Generally a soft spring gives a soft
riding feeling. Rebound damping
tends to become stronger and the
front fork may sink deeply over a se-
ries of gaps.

2. Use of stiff spring

• Change the rebound damping.
Turn in one or two clicks.
• Change the compression damp-
Do not install three or more adjust- ing.
ment washers for each front fork. Turn out one or two clicks.

Generally a stiff spring gives a stiff REAR SUSPENSION SETTING

riding feeling. Rebound damping The rear suspension setting should
Always adjust each front fork to
tends to become weaker, resulting in be made depending on the rider's
the same setting. Uneven adjust-
lack of a sense of contact with the feeling of an actual run and the circuit
ment can cause poor handling and
road surface or in a vibrating handle- conditions.
loss of stability.
bar. The rear suspension setting includes
the following two factors:
Standard washer quanti- FRONT FORK SETTING PARTS 1. Setting of spring preload
ty: • Adjustment washer "1" • Change the set length of the
Zero adjustment wash- spring.
TYPE (thick-
ers PART NUMBER • Change the spring.
ness)
Extent of adjustment: 2. Setting of damping force
Zero–2 adjustment T = 2.3 mm (0.09 • Change the rebound damping.
5XE-23364-00
washers in) • Change the compression damp-
ing.

4-6
 CHASSIS

CHOOSING SET LENGTH SETTING OF SPRING AFTER REAR SHOCK ABSORBER

1. Place a stand or block under the REPLACEMENT SETTING PARTS
engine to put the rear wheel After replacement, be sure to adjust • Rear shock spring "1"
above the floor, and measure the the spring to the set length [sunken SPRING
length "a" between the rear wheel length 90–100 mm (3.5–3.9 in)] and SPRI
PART I.D.
axle center and the rear fender set it. NG
TYPE NUM- MARK/
holding bolt. 1. Use of soft spring RAT
BER Q'TY
• Set the soft spring for less re- E
(-22212-)
bound damping to compensate
SOFT 4.3 5UN-00 Brown/1
for its less spring load. Run with
the rebound damping adjuster 4.5 5UN-10 Green/1
one or two clicks on the softer 4.7 5UN-20 Red/1
side and readjust it to suit your
4.9 5UN-30 Black/1
preference.
2. Use of stiff spring 5.1 5UN-40 Blue/1
2. Remove the stand or block from • Set the soft spring for more re- STD 5.3 5UN-50 Yellow/1
the engine and with a rider astride bound damping to compensate 5.5 5UN-60 Pink/1
the seat, measure the sunken for its greater spring load. Run
length "b" between the rear wheel with the rebound damping adjust- STIFF 5.7 5UN-70 White/1
axle center and the rear fender er one or two clicks on the stiffer
holding bolt. side and readjust it to suit your
• The I.D. mark "a" is marked at the
preference.
end of the spring.
• Spring specification varies accord-
Adjusting the rebound damping will ing to the color and quantity of I.D.
be followed more or less by a change marks.
in the compression damping. For cor-
rection, turn the low compression
damping adjuster on the softer side.

3. Loosen the locknut "1" and make

adjustment by turning the spring
When using a rear shock absorber
adjuster "2" to achieve the stan-
other than currently installed, use
dard figure from the subtraction of
the one whose overall length "a"
the length "b" from the length "a".
does not exceed the standard as it
Standard figure: may result in faulty performance.
90–100 mm (3.5–3.9 in) Never use one whose overall
length is greater than standard.

• If the machine is new and after it is Length "a" of standard

broken in, the same set length of shock:
the spring may change because of 488.5 mm (19.23 in)
the initial fatigue, etc. of the spring.
Therefore, be sure to make reeval-
uation.
• If the standard figure cannot be
achieved by adjusting the spring
adjuster and changing the spring
set length, replace the spring with
an optional one and make re-ad-
justment.

4-7
 CHASSIS

• Extent of adjustment (spring pre-

load)
SPRING
PART
NUM- Maximum Minimum
BER
(-22212-)
5UN-00 Position
5UN-10 in which
5UN-20 the spring
5UN-30 is turned
in 20 mm
(0.79 in) Position
from its in which
free the spring
length. is turned
in 1.5 mm
5UN-40 Position (0.06 in)
5UN-50 in which from its
5UN-60 the spring free
5UN-70 is turned length.
in 22 mm
(0.87 in)
from its
free
length.

For the spring preload adjustment, re-

fer to "ADJUSTING THE REAR
SHOCK ABSORBER SPRING PRE-
LOAD" in the CHAPTER 3.

4-8
 CHASSIS

SUSPENSION SETTING (FRONT FORK)

• If any of the following symptoms is experienced with the standard position as the base, make resetting by reference to
the adjustment procedure given in the same chart.
• Before any change, set the rear shock absorber sunken length to the standard figure 90–100 mm (3.5–3.9 in).

Section

Symptom Medi- Check Adjust

Large Small
Jump um
gap gap
gap
Compression damping Turn adjuster counterclockwise (about 2 clicks) to
Stiff over entire decrease damping.
○ ○ ○
range Oil level (oil amount) Decrease oil level by about 5–10 mm (0.2–0.4 in).
Spring Replace with soft spring.
Outer tube Check for any bends, dents, and other noticeable
Unsmooth move- scars, etc. If any, replace affected parts.
Inner tube
ment over entire ○ ○ ○ ○
range Under bracket tighten- Retighten to specified torque.
ing torque
Rebound damping Turn adjuster counterclockwise (about 2 clicks) to
Poor initial move- decrease damping.
○
ment
Oil seal Apply grease in oil seal wall.
Compression damping Turn adjuster clockwise (about 2 clicks) to in-
Soft over entire crease damping.
range, bottoming ○ ○
Oil level (oil amount) Increase oil level by about 5–10 mm (0.2–0.4 in).
out
Spring Replace with stiff spring.
Stiff toward stroke
○ Oil level (oil amount) Decrease oil level by about 5 mm (0.2 in).
end
Soft toward stroke
○ Oil level (oil amount) Increase oil level by about 5 mm (0.2 in).
end, bottoming out
Stiff initial move- Turn adjuster counterclockwise (about 2 clicks) to
○ ○ ○ ○ Compression damping
ment decrease damping.
Compression damping Turn adjuster clockwise (about 2 clicks) to in-
crease damping.
Rebound damping Turn adjuster counterclockwise (about 2 clicks) to
Low front, tending to decrease damping.
○ ○
lower front posture Balance with rear end Set sunken length for 95–100 mm (3.7–3.9 in)
when one passenger is astride seat (lower rear
posture).
Oil level (oil amount) Increase oil level by about 5 mm (0.2 in).
Compression damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
"Obtrusive" front, Balance with rear end Set sunken length for 90–95 mm (3.5–3.7 in)
tending to upper ○ ○ when one passenger is astride seat (upper rear
front posture posture).
Spring Replace with soft spring.
Oil level (oil amount) Decrease oil level by about 5–10 mm (0.2–0.4 in).

4-9
 CHASSIS

SUSPENSION SETTING (REAR SHOCK ABSORBER)

• If any of the following symptoms is experienced with the standard position as the base, make resetting by reference to
the adjustment procedure given in the same chart.
• Adjust the rebound damping in 2-click increments or decrements.
• Adjust the low compression damping in 1-click increments or decrements.
• Adjust the high compression damping in 1/6 turn increments or decrements.

Section

Symptom Medi- Check Adjust

Large Small
Jump um
gap gap
gap
Rebound damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Stiff, tending to sink ○ ○
Spring set length Set sunken length for 90–100 mm (3.5–3.9 in)
when one passenger is astride seat.
Rebound damping Turn adjuster clockwise (about 2 clicks) to in-
crease damping.
Spongy and unsta-
○ ○ Low compression Turn adjuster clockwise (about 1 click) to increase
ble
damping damping.
Spring Replace with stiff spring.
Rebound damping Turn adjuster counterclockwise (about 2 clicks) to
Heavy and dragging ○ ○ decrease damping.
Spring Replace with soft spring.
Rebound damping Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Low compression Turn adjuster clockwise (about 1 clicks) to in-
damping crease damping.
Poor road gripping ○ High compression Turn adjuster clockwise (about 1/6 turn) to in-
damping crease damping.
Spring set length Set sunken length for 90–100 mm (3.5–3.9 in)
when one passenger is astride seat.
Spring Replace with soft spring.
High compression Turn adjuster clockwise (about 1/6 turn) to in-
damping crease damping.
Bottoming out ○ ○ Spring set length Set sunken length for 90–100 mm (3.5–3.9 in)
when one passenger in astride seat.
Spring Replace with stiff spring.
Rebound damping Turn adjuster clockwise (about 2 clicks) to in-
Bouncing ○ ○ crease damping.
Spring Replace with soft spring.
High compression Turn adjuster counterclockwise (about 1/6 turn) to
damping decrease damping.
Stiff travel ○ ○ Spring set length Set sunken length for 90–100 mm (3.5–3.9 in)
when one passenger is astride seat.
Spring Replace with soft spring.

4-10
 RADIATOR

ENGINE
This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles
(e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are request-
ed not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to
servicing trouble and mechanical damage.

RADIATOR
REMOVING THE RADIATOR

Order Part name Q'ty Remarks

Refer to "CHECKING THE COOLANT" sec-
Drain the coolant.
tion in the CHAPTER 3.
Refer to "REMOVING THE SEAT, FUEL
Seat, fuel tank and left side cover TANK AND SIDE COVERS" section in the
CHAPTER 3.
1 Radiator guard 2
2 Radiator hose clamp 10 Only loosening.
3 Radiator hose 1 1
4 Left radiator 1
5 Radiator hose 3 1
6 Radiator pipe 2 1
7 Radiator hose 5 1

5-1
 RADIATOR

5
Order Part name Q'ty Remarks
8 Catch tank hose 1
9 Right radiator 1
10 Radiator hose 2 1
11 Radiator hose 4 1
12 Radiator pipe 1 1
13 Catch tank breather hose 1
14 Catch tank 1

5-2
 RADIATOR

HANDLING NOTE 2. Install: 5. Tighten:

• Catch tank hose "1" • Radiator hose clamp "4"
• Radiator hose 2 "2" Radiator hose clamp:
Do not remove the radiator cap • Radiator hose 3 "3"
when the engine and radiator are 2 Nm (0.2 m•kg, 1.4
• Radiator pipe 2 "4" ft•lb)
hot. Scalding hot fluid and steam • Radiator hose 5 "5"
may be blown out under pressure, • Radiator hose 4 "6"
which could cause serious injury. To right radiator "7".
When the engine has cooled, open
the radiator cap by the following
procedure:
Place a thick rag, like a towel, over
the radiator cap, slowly rotate the
cap counterclockwise to the de-
tent. This procedure allows any re- 6. Install:
sidual pressure to escape. When • Radiator guard "1"
the hissing sound has stopped, 3. Install:
press down on the cap while turn- • Right radiator "1" First fit the inner hook portion "a" and
ing counterclockwise and remove • Bolt (right radiator) "2" then the outer one "b" onto the radia-
it.
Bolt (right radiator): tor.
CHECKING THE RADIATOR 10 Nm (1.0 m•kg, 7.2
1. Inspect: ft•lb)
• Radiator core "1"
• Radiator hose 5 "3"
Obstruction → Blow out with com-
Refer to "CABLE ROUTING DIA-
pressed air through rear of the ra-
GRAM" section in the CHAPTER
diator.
2.
Bent fin → Repair/replace.

7. Install:
• Catch tank "1"
• Bolt (catch tank) "2"
Bolt (catch tank):
7 Nm (0.7 m•kg, 5.1
ft•lb)
4. Install:
INSTALLING THE RADIATOR • Bolt (catch tank) "3"
• Left radiator "1"
1. Install:
• Bolt (left radiator) "2" Bolt (catch tank):
• O-ring "1"
Bolt (left radiator): 16 Nm (1.6 m•kg, 11
• Radiator pipe 1 "2"
10 Nm (1.0 m•kg, 7.2 ft•lb)
• Bolt (radiator pipe) "3"
ft•lb) • Catch tank hose "4"
Bolt (radiator pipe):
10 Nm (1.0 m•kg, 7.2 • Radiator hose 1 "3" • Catch tank breather hose "5"
ft•lb) Refer to "CABLE ROUTING DIA-
Radiator hose 1: GRAM" section in the CHAPTER
2 Nm (0.2 m•kg, 1.4 2.
ft•lb)
Apply the lithium soap base grease
on the O-ring. Refer to "CABLE ROUTING DIA-
GRAM" section in the CHAPTER
2.

5-3
 CARBURETOR

CARBURETOR
REMOVING THE CARBURETOR

4 Nm (0.4 m kg, 2.9 ft lb)

2 Nm (0.2 m kg, 1.4 ft lb)

11 Nm (1.1 m kg, 8.0 ft lb)

4 Nm (0.4 m kg, 2.9 ft lb)

10 Nm (1.0 m kg, 7.2 ft lb)

3 Nm (0.3 m kg, 2.2 ft lb)

3 Nm (0.3 m kg, 2.2 ft lb)

Order Part name Q'ty Remarks

Refer to "REMOVING THE SEAT, FUEL
Seat and fuel tank TANK AND SIDE COVERS" section in the
CHAPTER 3.
Refer to "REAR SHOCK ABSORBER" sec-
Rear shock absorber
tion in the CHAPTER 6.
1 Clamp 2
2 Throttle position sensor lead coupler 1
3 Throttle cable cover 1
4 Throttle cable 2
5 Clamp (air filter joint) 1 Loosen the screw (air filter joint).
6 Clamp (carburetor joint) 1 Loosen the screws (carburetor joint).
7 Hot starter plunger 1
8 Carburetor assembly 1
9 Carburetor joint 1

5-4
 CARBURETOR

DISASSEMBLING THE CARBURETOR

Order Part name Q'ty Remarks

1 Carburetor breather hose 4
2 Valve lever housing cover 1
3 Screw (throttle shaft) 1
4 Throttle valve 1
5 Needle holder 1
6 Jet needle 1
7 Accelerator pump cover 1
8 Spring 1
9 Diaphragm (accelerator pump) 1
10 Air cut valve cover 1
11 Spring (air cut valve) 1
12 Diaphragm (air cut valve) 1
13 Float chamber 1
14 Leak jet 1
15 Pilot screw (For EUROPE) 1 Refer to removal section
16 Float pin 1
17 Float 1
18 Needle valve 1

5-5
 CARBURETOR

Order Part name Q'ty Remarks

19 Main jet 1
20 Needle jet 1
21 Spacer 1
22 Pilot jet 1
23 Starter jet 1
24 Push rod 1 Pull the push rod.
25 Throttle shaft assembly 1
26 Push rod link lever assembly 1
27 Main air jet 1
28 Pilot air jet 1
29 Cold starter plunger 1

5-6
 CARBURETOR

HANDLING NOTE 2. Inspect: CHECKING THE JET NEEDLE

• Main jet "1" 1. Inspect:
• Pilot jet "2" • Jet needle "1"
Do not loosen the screw (throttle • Needle jet "3" Bends/wear → Replace.
position sensor) "1" except when • Starter jet "4" • Clip groove
changing the throttle position sen- • Pilot air jet "5" Free play exists/wear → Replace.
sor due to failure because it will • Leak jet "6"
cause a drop in engine perfor- • Main air jet "7"
mance. Damage → Replace.
Contamination → Clean.

• Use a petroleum based solvent for

cleaning. Blow out all passages and
jets with compressed air.
• Never use a wire. MEASURING AND ADJUSTING
THE FLOAT HEIGHT
1. Measure:
REMOVING THE PILOT SCREW • Float height "a"
(For EUROPE) Out of specification → Adjust.
1. Remove: Float height:
• Pilot screw "1" 8.0 mm (0.31 in)

To optimize the fuel flow at a small

throttle opening, each machine's pilot CHECKING THE NEEDLE VALVE
screw has been individually set at the 1. Inspect:
factory. Before removing the pilot • Needle valve "1"
screw, turn it in fully and count the • Valve seat "2"
number of turns. Record this number Grooved wear "a" → Replace.
as the factory-set number of turns Dust "b" → Clean.
out. • Filter "c"
Clogged → Clean.
Measurement and adjustment
steps:
a. Hold the carburetor in an upside
down position.

• Slowly tilt the carburetor in the op-

posite direction, then take the mea-
CHECKING THE CARBURETOR surement when the needle valve
1. Inspect: CHECKING THE THROTTLE aligns with the float arm.
• Carburetor body VALVE • If the carburetor is level, the weight
Contamination → Clean. 1. Check: of the float will push in the needle
• Free movement valve, resulting in an incorrect mea-
Stick → Repair or replace. surement.
• Use a petroleum based solvent for
cleaning. Blow out all passages and b. Measure the distance between
jets with compressed air. Insert the throttle valve "1" into the the mating surface of the float
• Never use a wire. carburetor body, and check for free chamber and top of the float using
movement. a vernier calipers.

The float arm should be resting on the

needle valve, but not compressing
the needle valve.

c. If the float height is not within

specification, inspect the valve
seat and needle valve.
d. If either is worn, replace them
both.

5-7
 CARBURETOR

e. If both are fine, adjust the float 2. Inspect:

height by bending the float tab "b" • Throttle shaft "1"
on the float. • Spring "2"
• Lever 1 "3"
• Spring 1 "4"
• Lever 2 "5"
• Spring 2 "6"
Dirt → Clean.
4. Install:
• Spring 2 "1"
To lever 2 "2".
f. Recheck the float height.

CHECKING THE FLOAT

1. Inspect:
• Float "1"
CHECKING THE AIR CUT VALVE
Damage → Replace.
1. Inspect:
• Diaphragm (air cut valve) "1"
• Spring (air cut valve) "2" 5. Install:
• Air cut valve cover "3" • Push rod link lever assembly "1"
• O-ring "4"
Tears (diaphragm)/damage→Re- Make sure the stopper "a" of the
place. spring 2 fits into the recess "b" in the
carburetor.
CHECKING THE STARTER
PLUNGER
1. Inspect:
• Cold starter plunger "1"
• Hot starter plunger "2"
Wear/damage → Replace.
ASSEMBLING THE CARBURETOR
1. Install:
• Cold starter plunger "1" 6. Install:
• Washer "1"
• Circlip "2"

CHECKING THE ACCELERATOR

PUMP
1. Inspect:
• Diaphragm (accelerator pump)
2. Install:
"1"
• Pilot air jet "1"
• Spring (accelerator pump) "2" 7. Install:
• Main air jet "2"
• Accelerator pump cover "3" • Spring "1"
• O-ring "4" To throttle shaft "2".
• Push rod "5"
Tears (diaphragm)/damage→Re-
Install the bigger hook "a" of the
place.
spring fits on the stopper "b" of the
Dirt → Clean.
throttle shaft pulley.

3. Install:
• Spring 1 "1"
• Lever 1 "2"
To lever 2 "3".

Make sure the spring 1 fits on the

stopper "a" of the lever 2.

5-8
 CARBURETOR

8. Install: 10. Install: 13. Install:

• Throttle shaft assembly "1" • Starter jet "1" • O-ring
• Washer (metal) "2" • Pilot jet "2" • Leak jet "1"
• Washer (resin) "3" • Spacer "3" • Float chamber "2"
• Valve lever "4" • Needle jet "4" • Bolt (float chamber) "3"
• Main jet "5" • Cable holder (throttle stop screw
• Apply the fluorochemical grease on cable) "4"
the bearings. • Hose holder (carburetor breather
• Fit the projection "a" on the throttle hose) "5"
shaft assembly into the slot "b" in
the throttle position sensor.
• Make sure the stopper "c" of the
spring fits into the recess in the car-
buretor.
• Turn the throttle shaft assembly left 11. Install:
while holding down the lever 1 "5" • Needle valve "1"
and fit the throttle stop screw tip "d" • Float "2"
to the stopper "e" of the throttle • Float pin "3" 14. Install:
shaft assembly pulley. • Diaphragm (air cut valve) "1"
• After installing the needle valve to • Spring (air cut valve) "2"
the float, install them to the carbure- • O-ring "3"
tor. • Air cut valve cover "4"
• Check the float for smooth move- • Holder (cylinder head breather
ment. hose) "5"
• Screw (air cut valve cover) "6"

12. Install: (For EUROPE) 15. Install:

• Pilot screw "1" • Diaphragm (accelerator pump)
• Spring "2" "1"
• Washer "3" • Spring "2"
• O-ring "4" • O-ring "3"
• Accelerator pump cover "4"
• Hose holder (drain hose) "5"
• Screw (accelerator pump cover)
"6"

Install the diaphragm (accelerator

9. Install: pump) with its mark "a" facing the
• Push rod "1" spring.

While holding down the lever 1 "2", in- Note the following installation
sert the push rod farthest into the car- points:
buretor. a. Turn in the pilot screw until it is
lightly seated.
b. Turn out the pilot screw by the
number of turns recorded before
removing.
Pilot screw (example):
2 turns out

5-9
 CARBURETOR

16. Install: ADJUSTING THE ACCELERATOR

• Jet needle "1" PUMP TIMING
• Collar "2"
• Spring "3" Adjustment steps:
• Needle holder "4"
• Throttle valve plate "5"
In order for the throttle valve height
To throttle valve "6".
"a" to achieve the specified value,
tuck under the throttle valve plate "1"
3. Install:
the rod "2" etc. with the same outer di-
• Hot starter plunger "1"
ameter as the specified value.
Hot starter plunger:
Throttle valve height: 2 Nm (0.2 m•kg, 1.4
0.8 mm (0.031 in) ft•lb)

17. Install:
• Throttle valve assembly "1"
• Screw (throttle shaft) "2"

Install the valve lever rollers "3" into

the slits "a" of the throttle valve.

4. Tighten:
a. Fully turn in the accelerator pump
• Bolt (carburetor joint) "1"
adjusting screw "3".
b. Check that the link lever "4" has Bolt (carburetor joint):
free play "b" by pushing lightly on 3 Nm (0.3 m•kg, 2.2
it. ft•lb)
• Bolt (air filter joint) "2"
Bolt (air filter joint):
18. Install: 3 Nm (0.3 m•kg, 2.2
• O-ring "1" ft•lb)
• Valve lever housing cover "2"
• Bolt (valve lever housing cover)
"3"
c. Gradually turn out the adjusting
screw while moving the link lever
until it has no more free play.

INSTALLING THE CARBURETOR

1. Install: 5. Install:
• Carburetor joint "1" • Throttle cable (pull) "1"
19. Install: Throttle cable (pull):
Carburetor joint:
• Carburetor breather hose "1" 4 Nm (0.4 m•kg, 2.9
10 Nm (1.0 m•kg, 7.2
ft•lb) ft•lb)
Install the carburetor breather hoses
to the carburetor so that the hoses do • Throttle cable (return) "2"
not bend near where they are in- Throttle cable (return):
stalled. 11 Nm (1.1 m•kg, 8.0
ft•lb)

2. Install:
• Carburetor "1"

Install the projection "a" between the

carburetor joint slots.

5-10
 CARBURETOR

6. Adjust:
• Throttle grip free play
Refer to "ADJUSTING THE
THROTTLE GRIP FREE PLAY"
section in the CHAPTER 3.
7. Install:
• Throttle cable cover "1"
• Bolt (throttle cable cover) "2"
Bolt (throttle cable cov-
er):
4 Nm (0.4 m•kg, 2.9
ft•lb)

8. Install:
• Throttle position sensor lead cou-
pler "1"
• Clamp "2"
Refer to "CABLE ROUTING DIA-
GRAM" section in the CHAPTER
2.

9. Install:
• Clamp "1"
Refer to "CABLE ROUTING DIA-
GRAM" section in the CHAPTER
2.

5-11
 AIR INDICTOIN SYSTEM

AIR INDICTOIN SYSTEM

REMOVING THE AIR INDUCTION SYSTEM

7 Nm (0.7 m kg, 5.1 ft lb)

10 Nm (1.0 m kg, 7.2 ft lb)

4 Nm (0.4 m kg, 2.9 ft lb)

Order Part name Q'ty Remarks

1 Bracket 1
2 Air cut-off valve assembly 1
Air induction hose (air cut-off valve - front of cyl-
3 1
inder head)
4 Air induction pipe 1
5 Gasket 1
Air induction hose (air cut-off valve - rear of cylin-
6 1
der head)
Air induction hose (air cut-off valve - air filter
7 1
case)

5-12
 AIR INDICTOIN SYSTEM

CHECKING THE AIR INDUCTION

SYSTEM
1. Inspect:
• Air induction hose
Crack/damage → Replace.
• Air induction pipe
Crack/damage → Replace.
2. Check:
• Operation of air cut valve a. From air filter
Pass air through the pipe and b. To cylinder head (exhaust
check the air cut valve for opera- port)
tion. c. From cylinder head (intake
Does not meet the following con- port)
dition → Replace the air cut valve A. Check for induction from air
assembly. filter.
"a" to "b" Air passes. B. Check for prevention of back-
flow into air filter.
"b" to "a" Air does not pass. C. Check for prevention of after-
Air does not pass burn. (When throttle is closed
"a" to "b" when specified pres- at sudden deceleration)
sure is on "c".

• Blow in air to check for operation.

• When using vacuum, check by the
use of the vacuum/pressure pump
gauge set "1".

Vacuum/pressure pump
gauge set:
YB-35956-A/90890-
06756

Vacuum specifying pres-

sure:
46.7–86.7 kPa (350–650
mmHg, 13.8–25.6 inHg)

When using vacuum on the pipe

"c", take care not to exceed the
specified value.

5-13
 CAMSHAFTS

CAMSHAFTS
REMOVING THE CYLINDER HEAD COVER

Order Part name Q'ty Remarks

Refer to "REMOVING THE SEAT, FUEL
Seat and fuel tank TANK AND SIDE COVERS" section in the
CHAPTER 3.
Air cut-off valve assembly Refer to "AIR INDUCTION SYSTEM" section.
1 Spark plug 1
2 Cylinder head breather hose 1
3 Bolt (cylinder head cover) 2
4 Cylinder head cover 1
5 Cylinder head cover gasket 1
6 Timing chain guide (top side) 1

5-14
 CAMSHAFTS

REMOVING THE CAMSHAFTS

Order Part name Q'ty Remarks

1 Timing mark accessing screw 1 Refer to removal section.
2 Crankshaft end accessing screw 1 Refer to removal section.
3 Timing chain tensioner cap bolt 1 Refer to removal section.
4 Timing chain tensioner 1 Refer to removal section.
5 Camshaft cap 2 Refer to removal section.
6 Clip 2 Refer to removal section.
7 Exhaust camshaft 1 Refer to removal section.
8 Intake camshaft 1 Refer to removal section.

5-15
 CAMSHAFTS

REMOVING THE CAMSHAFT 3. Remove: CHECKING THE CAMSHAFT

1. Remove: • Timing chain tensioner cap bolt 1. Inspect:
• Timing mark accessing screw "1" "1" • Cam lobe
• Crankshaft end accessing screw • Timing chain tensioner "2" Pitting/scratches/blue discolor-
"2" • Gasket ation → Replace.
2. Measure:
• Cam lobe length "a" and "b"
Out of specification → Replace.
Cam lobes length:
Intake "a":
29.65–29.75 mm
(1.1673–1.1713 in)
<Limit>:
2. Align: 4. Remove: 29.55 mm (1.1634 in)
• T.D.C. mark • Bolt (camshaft cap) "1" Intake "b":
With align mark. • Camshaft cap "2" 22.45–22.55 mm
• Clip (0.8839–0.8878 in)
Checking steps: <Limit>:
a. Turn the crankshaft counterclock- Remove the bolts (camshaft cap) in a 22.35 mm (0.8799 in)
wise with a wrench. crisscross pattern, working from the Exhaust "a":
b. Align the T.D.C. mark "a" on the outside in. 30.399–30.499 mm
rotor with the align mark "b" on the (1.1968–1.2007 in)
crankcase cover when piston is at <Limit>:
T.D.C. on compression stroke. The bolts (camshaft cap) must be 30.299 mm (1.1929 in)
removed evenly to prevent dam- Exhaust "b":
In order to be sure that the piston is at age to the cylinder head, cam- 22.45–22.55 mm
Top Dead Center, the punch mark "c" shafts or camshaft caps. (0.8839–0.8878 in)
on the exhaust camshaft and the <Limit>:
punch mark "d" on the intake cam- 22.35 mm (0.8799 in)
shaft must align with the cylinder
head surface, as shown in the illustra-
tion.

5. Remove:
• Exhaust camshaft "1"
• Intake camshaft "2"

Attach a wire "3" to the timing chain to

prevent it from falling into the crank-
case.

3. Measure:
• Runout (camshaft)
Out of specification → Replace.
Runout (camshaft):
Less than 0.03 mm
(0.0012 in)

5-16
 CAMSHAFTS

4. Measure:
• Camshaft-to-cap clearance
Out of specification → Measure
camshaft outside diameter.
Camshaft-to-cap clear-
ance:
0.028–0.062 mm
(0.0011–0.0024 in)
<Limit>:0.08 mm (0.003 CHECKING THE CAMSHAFT
in) SPROCKET
1. Inspect:
• Camshaft sprocket "1"
Measurement steps: Wear/damage → Replace the
a. Install the camshaft onto the cylin- camshaft assembly and timing
der head. chain as a set.
b. Position a strip of Plastigauge®
"1" onto the camshaft. INSTALLING THE CAMSHAFT
1. Install:
• Exhaust camshaft "1"
• Intake camshaft "2"

CHECKING THE
DECOMPRESSION SYSTEM
c. Install the clip, dowel pins and 1. Check:
camshaft caps. • Decompression system
Bolt (camshaft cap):
10 Nm (1.0 m•kg, 7.2 Checking steps:
ft•lb) a. Check that the decompression Installation steps:
mechanism cam "1" moves a. Turn the crankshaft counterclock-
smoothly. wise with a wrench.
• Tighten the bolts (camshaft cap) in b. Check that the decompression
a crisscross pattern from innermost mechanism cam lever pin "2" proj- • Apply the molybdenum disulfide oil
to outer caps. ects from the camshaft. on the camshafts.
• Do not turn the camshaft when • Apply the engine oil on the decom-
measuring clearance with the Plas- pression system.
tigauge®. • Squeezing the decompression le-
ver allows the crankshaft to be
d. Remove the camshaft caps and
turned easily.
measure the width of the Plasti-
gauge® "1". b. Align the T.D.C. mark "a" on the
rotor with the align mark "b" on the
crankcase cover when piston is at
T.D.C. on compression stroke.
CHECKING THE TIMING CHAIN
TENSIONER
1. Check:
• While pressing the tensioner rod
lightly with fingers, use a thin
screwdriver "1" and wind the ten-
sioner rod up fully clockwise.
5. Measure:
• When releasing the screwdriver
• Camshaft outside diameter "a"
by pressing lightly with fingers, c. Fit the timing chain "3" onto both
Out of specification→Replace the
make sure that the tensioner rod camshaft sprockets and install the
camshaft.
will come out smoothly. camshafts on the cylinder head.
Within specification → Replace
• If not, replace the tensioner as-
camshaft case and camshaft
sembly.
caps as a set.
Camshaft outside diame-
ter:
21.959–21.972 mm
(0.8645–0.8650 in)

5-17
 CAMSHAFTS

5. Install:
The camshafts should be installed Installation steps: • Timing mark accessing screw "1"
onto the cylinder head so that the a. While pressing the tensioner rod • Crankshaft end accessing screw
punch mark "c" on the exhaust cam- lightly with fingers, use a thin "2"
shaft and the punch mark "d" on the screwdriver and wind the tension-
intake camshaft must align with the er rod up fully clockwise.
cylinder head surface, as shown in
the illustration.

6. Install:
• Timing chain guide (top side) "1"
b. With the rod fully wound and the • Cylinder head cover gasket "2"
chain tensioner UP mark "a" fac- • Cylinder head cover "3"
ing upward, install the gasket "1" • Bolt (cylinder head cover) "4"
and the timing chain tensioner "2", Bolt (cylinder head cov-
Do not turn the crankshaft during and tighten the bolt "3" to the er):
the camshaft installation. Damage specified torque. 10 Nm (1.0 m•kg, 7.2
or improper valve timing will re- Bolt (timing chain ten- ft•lb)
sult. sioner):
10 Nm (1.0 m•kg, 7.2
d. Install the clips, camshaft caps "4" Apply the sealant on the cylinder
ft•lb)
and bolts (camshaft cap) "5". head cover gasket.
Bolt (camshaft cap):
10 Nm (1.0 m•kg, 7.2 YAMAHA Bond No. 1215
ft•lb) (ThreeBond® No. 1215):
90890-85505

c. Release the screwdriver, check

the tensioner rod to come out and
tighten the gasket "4" and the cap
bolt "5" to the specified torque.
Tensioner cap bolt:
• Before installing the clips, cover the 7 Nm (0.7 m•kg, 5.1
cylinder head with a clean rag to ft•lb)
prevent the clips from into the cylin-
der head cavity.
• Apply the molybdenum disulfide oil
on the thread of the bolts (camshaft
cap).
• Tighten the bolts to the specified 7. Install:
torque in two or three steps in the • Cylinder head breather hose
proper tightening sequence as • Spark plug
shown.
Spark plug:
13 Nm (1.3 m•kg, 9.4
3. Turn:
ft•lb)
The bolts (camshaft cap) must be • Crankshaft
tightened evenly, or damage to the Counterclockwise several turns.
cylinder head, camshaft caps, and 4. Check:
camshaft will result. • Rotor T.D.C. mark
Align with the crankcase align
mark.
2. Install: • Camshaft match marks
• Timing chain tensioner Align with the cylinder head sur-
face.
Out of alignment → Adjust.

5-18
 CYLINDER HEAD

CYLINDER HEAD
REMOVING THE CYLINDER HEAD

Order Part name Q'ty Remarks

Refer to "REMOVING THE SEAT, FUEL
Seat and fuel tank TANK AND SIDE COVERS" section in the
CHAPTER 3.
Refer to "REMOVING THE EXHAUST PIPE
Exhaust pipe and silencer
AND SILENCER" section in the CHAPTER 3.
Radiator hose 1 Disconnect at cylinder head side.
Carburetor Refer to "CARBURETOR" section.
Air cut-off valve assembly Refer to "AIR INDUCTION SYSTEM" section.
Camshaft Refer to "CAMSHAFTS" section.
Upper engine bracket Refer to "ENGINE REMOVAL" section.
1 Radiator pipe 1
2 Oil delivery pipe 1
3 Nut 2
4 Bolt [L = 135 mm (5.31 in)] 2
5 Bolt [L = 145 mm (5.71 in)] 2
6 Cylinder head 1
7 Timing chain guide (exhaust side) 1

5-19
 CYLINDER HEAD

CHECKING THE CYLINDER HEAD INSTALLING THE CYLINDER

1. Eliminate: HEAD
• Carbon deposits (from the com- 1. Install:
bustion chambers) • Dowel pin "1"
Use a rounded scraper. • Cylinder head gasket "2"
• Timing chain guide (exhaust side)
Do not use a sharp instrument to "3"
avoid damaging or scratching: • Cylinder head "4"
• Spark plug threads 3. Install:
• Valve seats While pulling up the timing chain, in- • Copper washer "1"
stall the timing chain guide (exhaust • Oil delivery pipe "2"
side) and cylinder head. • Union bolt (M8) "3"
Union bolt (M8):
18 Nm (1.8 m•kg, 13
ft•lb)
• Union bolt (M10) "4"
Union bolt (M10):
20 Nm (2.0 m•kg, 14
2. Inspect:
ft•lb)
• Cylinder head
Scratches/damage → Replace. 2. Install:
• Washer "1" First tighten the union bolts temporar-
Replace the titanium valves with the • Cable guide "2" ily. Then retighten them with the width
cylinder head. • Bolts [L = 145 mm (5.71 in)] "3" "a" across flats of the oil delivery pipe
Bolts [L = 145 mm (5.71 held tight with a spanner.
Refer to "CHECKING THE
in)]:
VALVE".
38 Nm (3.8 m•kg, 27
3. Measure:
ft•lb)
• Cylinder head warpage
Out of specification → Resurface. • Bolts [L = 135 mm (5.31 in)] "4"
Cylinder head warpage: Bolts [L = 135 mm (5.31
Less than 0.05 mm in)]:
(0.002 in) 38 Nm (3.8 m•kg, 27
ft•lb)
4. Install:
Warpage measurement and resur- • Nuts "5" • Radiator pipe "1"
facing steps: Nuts: • Bolt (radiator pipe) "2"
a. Place a straightedge and a feeler 10 Nm (1.0 m•kg, 7.2 Bolt (radiator pipe):
gauge across the cylinder head. ft•lb) 10 Nm (1.0 m•kg, 7.2
b. Use a feeler gauge to measure ft•lb)
the warpage.
c. If the warpage is out of specifica- • Apply the molybdenum disulfide
tion, resurface the cylinder head. grease on the thread and contact
d. Place a 400–600 grit wet sandpa- surface of the bolts.
per on the surface plate, and re- • Follow the numerical order shown
surface the head using a figure- in the illustration. Tighten the bolts
eight sanding pattern. and nuts in two stages.

To ensure an even surface rotate the

cylinder head several times.

5-20
 VALVES AND VALVE SPRINGS

VALVES AND VALVE SPRINGS

REMOVING THE VALVES AND VALVE SPRINGS

Order Part name Q'ty Remarks

Cylinder head Refer to "CYLINDER HEAD" section.
1 Valve lifter 5 Refer to removal section.
2 Adjusting pad 5 Refer to removal section.
3 Valve cotter 10 Refer to removal section.
4 Valve spring retainer 5
5 Valve spring 5
6 Valve stem seal 5
7 Valve spring seat 5
8 Exhaust valve 2
9 Intake valve 3

5-21
 VALVES AND VALVE SPRINGS

REMOVING THE VALVE LIFTER a. Remove the valve guide using a

AND VALVE COTTER Valve spring compres- valve guide remover "1".
sor:
1. Remove:
YM-4019/90890-04019
• Valve lifter "1" Valve spring compressor
• Pad "2" adapter 19.5 mm:
YM-04114
Identify each lifter "1" and pad "2" po- Valve spring compressor
sition very carefully so that they can attachment:
be reinstalled in their original place. 90890-04114

b. Install the new valve guide using a

valve guide remover "1" and valve
guide installer "2".
Valve guide installation
height "a":
Intake:
11.8–12.2 mm (0.46–
0.48 in)
CHECKING THE VALVE Exhaust:
2. Check: 1. Measure: 11.3–11.7 mm (0.44–
• Valve sealing • Stem-to-guide clearance 0.46 in)
Leakage at the valve seat → In-
Stem-to-guide clearance = valve
spect the valve face, valve seat
guide inside diameter "a" -
and valve seat width. valve stem diameter "b"
Out of specification→Replace the
Checking steps:
valve guide.
a. Pour a clean solvent "1" into the
intake and exhaust ports. Clearance (stem to
b. Check that the valve seals prop- guide):
erly. Intake:
0.010–0.037 mm c. After installing the valve guide,
There should be no leakage at the bore the valve guide using a valve
(0.0004–0.0015 in)
valve seat "2". guide reamer "3" to obtain proper
<Limit>:0.08 mm
(0.003 in) stem-to-guide clearance.
Exhaust:
0.025–0.052 mm
(0.0010–0.0020 in)
<Limit>:0.10 mm
(0.004 in)

Valve guide remover:

Intake:4.0 mm (0.16 in)
YM-4111/90890-04111
Exhaust:4.5 mm (0.18
in)
YM-4116/90890-04116
Valve guide installer:
Intake:4.0 mm (0.16 in)
3. Remove: YM-4112/90890-04112
• Valve cotter Exhaust:4.5 mm (0.18
in)
Remove the valve cotters by com- YM-4117/90890-04117
pressing the valve spring with the Valve guide reamer:
valve spring compressor “1” and the 2. Replace: Intake:4.0 mm (0.16 in)
valve spring compressor attachment • Valve guide YM-4113/90890-04113
“2”. Exhaust:4.5 mm (0.18
in)
Replacement steps: YM-4118/90890-04118

To ease guide removal, installation

and to maintain correct fit heat the After replacing the valve guide reface
cylinder head in an over to 100 °C the valve seat.
(212 °F).

5-22
 VALVES AND VALVE SPRINGS

3. Inspect: • When replacing the valves or valve

• Valve face Valve seat width: guides, use new valves to lap the
Pitting/wear → Grind the face. Intake: valve seats, and then replace them
• Valve stem end 0.9–1.1 mm (0.0354– with new valves.
Mushroom shape or diameter 0.0433 in)
larger than the body of the stem → <Limit>:1.6 mm
Replace. (0.0630 in) Lapping steps:
4. Measure: Exhaust: a. Apply a coarse lapping compound
• Margin thickness "a" 0.9–1.1 mm (0.0354– to the valve face.
Out of specification → Replace. 0.0433 in)
<Limit>:1.6 mm
Margin thickness: (0.0630 in) Do not let the compound enter the
Intake: gap between the valve stem and
0.8 mm (0.0315 in) the guide.
Exhaust:
0.7 mm (0.0276 in)

Measurement steps:
a. Apply Mechanic's blueing dye b. Apply molybdenum disulfide oil to
(Dykem) "b" to the valve face. the valve stem.
5. Measure:
• Runout (valve stem)
Out of specification → Replace.
Runout limit:
0.01 mm (0.0004 in)

• When installing a new valve always

replace the guide. b. Install the valve into the cylinder c. Install the valve into the cylinder
• If the valve is removed or replaced head. head.
always replace the oil seal. c. Press the valve through the valve d. Turn the valve until the valve face
guide and onto the valve seat to and valve seat are evenly pol-
make a clear pattern. ished, then clean off all of the
d. Measure the valve seat width. compound.
Where the valve seat and valve
face made contact, blueing will For best lapping results, lightly tap
have been removed. the valve seat while rotating the valve
e. If the valve seat is too wide, too back and forth between your hands.
narrow, or the seat is not cen-
tered, the valve seat must be
6. Eliminate:
refaced.
• Carbon deposits
(from the valve face and valve
seat) 9. Lap:
7. Inspect: • Valve face
• Valve seat • Valve seat
Pitting/wear → Reface the valve
seat. e. Apply a fine lapping compound to
This model uses titanium intake
8. Measure: the valve face and repeat the
and exhaust valves. Titanium
• Valve seat width "a" above steps.
valves that have been used to lap
Out of specification → Reface the
the valve seats must not be used.
valve seat. After every lapping operation be sure
Always replace lapped valves with
new valves. to clean off all of the compound from
the valve face and valve seat.

• When replacing the cylinder head, f. Apply Mechanic's blueing dye

replace the valves without lapping (Dykem) to the valve face.
the valve seats and valve faces. g. Install the valve into the cylinder
head.

5-23
 VALVES AND VALVE SPRINGS

h. Press the valve through the valve 3. Install:

guide and onto the valve seat to • Valve cotter
make a clear pattern.
i. Measure the valve seat width Install the valve cotters by compress-
again. If the valve seat width is out ing the valve spring with the valve
of specification, reface and relap spring compressor “1” and the valve
the valve seat. spring compressor attachment “2”.
CHECKING THE VALVE LIFTERS
CHECKING THE VALVE SPRINGS Valve spring compres-
1. Inspect:
1. Measure: sor:
• Valve lifter
• Valve spring free length "a" YM-4019/90890-04019
Scratches/damage → Replace
Out of specification → Replace. Valve spring compressor
both lifters and cylinder head.
Free length (valve adapter 19.5 mm:
spring): YM-04114
Intake: Valve spring compressor
36.58 mm (1.44 in) attachment:
<Limit>: 35.58 mm 90890-04114
(1.40 in)
Exhaust:
37.54 mm (1.48 in)
<Limit>: 36.54 mm INSTALLING THE VALVES
(1.44 in) 1. Apply:
• Molybdenum disulfide oil
Onto the valve stem and valve
stem seal.
2. Install: 4. To secure the valve cotters onto
• Valve "1" the valve stem, lightly tap the
• Valve spring seat "2" valve tip with a piece of wood.
• Valve stem seal "3"
• Valve spring "4"
2. Measure: • Valve spring retainer "5" Hitting the valve tip with excessive
• Compressed spring force "a" To cylinder head. force could damage the valve.
Out of specification → Replace.
Compressed spring • Make sure that each valve is in-
force: stalled in its original place, also re-
Intake: ferring to the painted color as
113.00–118.60 N at follows.
29.13 mm (10.50– Intake (middle) "a": Orange
12.09 kg at 29.13 mm, Intake (right/left) "b": Green
23.15–26.66 lb at 1.15 Exhaust "c": Purple
in) • Install the valve springs with the
5. Install:
Exhaust: larger pitch "d" facing upward.
• Adjusting pad "1"
126.00–144.00 N at • Valve lifter "2"
29.30 mm (12.85–
14.68 kg at 29.30 mm,
28.32–32.37 lb at 1.15 • Apply the molybdenum disulfide oil
in) on the valve stem end.
• Apply the engine oil on the valve lift-
ers.
• Valve lifter must turn smoothly
when rotated with a finger.
• Be careful to reinstall valve lifters
and pads in their original place.

b. Installed length
3. Measure:
• Spring tilt "a"
Out of specification → Replace. e. Smaller pitch
Spring tilt limit:
Intake:
2.5°/1.6 mm (0.063 in)
Exhaust:
2.5°/1.6 mm (0.063 in)

5-24
 CYLINDER AND PISTON

CYLINDER AND PISTON

REMOVING THE CYLINDER AND PISTON

Order Part name Q'ty Remarks

Cylinder head Refer to "CYLINDER HEAD" section.
1 Bolt (cylinder) 1
2 Cylinder 1
3 Piston pin clip 2 Refer to removal section.
4 Piston pin 1 Refer to removal section.
5 Piston 1 Refer to removal section.
6 Piston ring set 1 Refer to removal section.

5-25
 CYLINDER AND PISTON

REMOVING THE PISTON AND CHECKING THE CYLINDER AND d. If out of specification, replace the
PISTON RING PISTON piston and piston rings as a set.
1. Remove: 1. Inspect: e. Calculate the piston-to-cylinder
• Piston pin clip "1" • Cylinder and piston walls clearance with following formula:
• Piston pin "2" Vertical scratches → Replace cyl- Piston-to-cylinder clearance =
• Piston "3" inder and piston. Cylinder bore "C" - Piston skirt
2. Measure: diameter "P"
• Put identification marks on each • Piston-to-cylinder clearance
piston head for reference during re- Piston-to-cylinder clear-
installation. Measurement steps: ance:
• Before removing each piston pin, a. Measure the cylinder bore "C" 0.030–0.055 mm
deburr the clip groove and pin hole with a cylinder bore gauge. (0.0012–0.0022 in)
area. If the piston pin groove is de- <Limit>:0.1 mm (0.004
burred and the piston pin is still dif- in)
Measure the cylinder bore "C" in par-
ficult to remove, use the piston pin allel to and at right angles to the f. If out of specification, replace the
puller set "4". crankshaft. Then, find the average of cylinder, and replace the piston
the measurements. and piston rings as set.
Piston pin puller set:
YU-1304/90890-01304 77.00–77.01
Cylinder bore CHECKING THE PISTON RING
mm (3.0315– 1. Measure:
"C"
3.0319 in) • Ring side clearance
Do not use a hammer to drive the 0.05 mm (0.002 Use a feeler gauge "1".
piston pin out. Taper limit "T"
in) Out of specification→Replace the
Out of round 0.05 mm (0.002 piston and rings as a set.
"R" in)
Clean carbon from the piston ring
"C" = Maximum D grooves and rings before measuring
"T" = (Maximum D1 or D2) - (Max- the side clearance.
imum D5 or D6)
"R" = (Maximum D1, D3 or D5) - Side clearance:
(Minimum D2, D4 or D6) Standard <Limit>
0.12
0.030–0.065
Top mm
mm (0.0012–
ring (0.005
0.0026 in)
in)
0.12
0.020–0.055
2nd mm
mm (0.0008–
ring (0.005
2. Remove: 0.0022 in)
in)
• Piston ring "1" b. If out of specification, replace the
cylinder, and replace the piston
and piston rings as set.
Spread the end gaps apart while at
c. Measure the piston skirt diameter
the same time lifting the piston ring
"P" with a micrometer.
over the top of the piston crown, as
shown in the illustration.

2. Position:
• Piston ring
(in cylinder)

a. 8 mm (0.31 in) from the piston Insert a ring into the cylinder and
bottom edge push it approximately 10 mm (0.39 in)
into the cylinder. Push the ring with
Piston size "P"
the piston crown so that the ring will
76.955–76.970 be at a right angle to the cylinder
Standard mm (3.0297– bore.
3.0303 in)

5-26
 CYLINDER AND PISTON

b. Measure the inside diameter (pis-

ton) "b".
Inside diameter (piston):
16.002–16.013 mm
(0.6300–0.6304 in)

a. 10 mm (0.39 in) a. Top ring end

3. Measure: b. 2nd ring end
• Ring end gap c. Oil ring end (upper)
Out of specification → Replace. d. Oil ring
e. Oil ring end (lower)
You cannot measure the end gap on 3. Install:
the expander spacer of the oil control c. Calculate the piston pin-to-piston • Piston "1"
ring. If the oil control ring rails show clearance with the following for- • Piston pin "2"
excessive gap, replace all three rings. mula. • Piston pin clip "3"
Piston pin-to-piston clearance =
End gap: Inside diameter (piston) "b" - • Apply engine oil onto the piston pin
Outside diameter (piston pin) and piston.
Standard <Limit>
"a" • Be sure that the arrow mark "a" on
0.50 the piston points to the exhaust side
Top 0.15–0.25 mm mm d. If out of specification, replace the of the engine.
ring (0.006–0.010 in) (0.020 piston. • Before installing the piston pin clip,
in) Piston pin-to-piston cover the crankcase with a clean
0.80 clearance: rag to prevent the piston pin clip
2nd 0.30–0.45 mm mm 0.002–0.022 mm from falling into the crankcase.
ring (0.012–0.018 in) (0.031 (0.0001–0.0009 in) • Install the piston pin clips with their
in) <Limit>:0.07 mm (0.003 ends facing downward.
in)
Oil 0.10–0.40 mm
—
ring (0.004–0.016 in)
CHECKING THE PISTON PIN INSTALLING THE PISTON RING
1. Inspect: AND PISTON
• Piston pin 1. Install:
Blue discoloration/grooves → Re- • Piston ring
place, then inspect the lubrication Onto the piston.
system.
2. Measure: • Be sure to install the piston rings so
• Piston pin-to-piston clearance that the manufacturer's marks or
numbers are located on the upper
Measurement steps: side of the rings.
a. Measure the outside diameter • Lubricate the piston and piston
(piston pin) "a". rings liberally with engine oil. New
If out of specification, replace the
piston pin.
Outside diameter (piston
pin):
15.991–16.000 mm
(0.6296–0.6299 in)

2. Position:
• Top ring
• 2nd ring
• Oil ring
Offset the piston ring end gaps as
shown.

5-27
 CYLINDER AND PISTON

INSTALLING THE CYLINDER

1. Lubricate:
• Piston
• Piston ring
• Cylinder

Apply a liberal coating of engine oil.

2. Install:
• Dowel pin "1"
• O-ring "2"

Apply the lithium soap base grease

on the O-ring.

3. Install:
• Cylinder gasket "1"
• Cylinder "2"

Install the cylinder with one hand

while compressing the piston rings
with the other hand.

• Pass the timing chain "3"

through the timing chain cavity.
• Be careful not to damage the tim-
ing chain guide "4" during instal-
lation.

4. Install:
• Bolt (cylinder) "5"
Bolt (cylinder):
10 Nm (1.0 m•kg, 7.2
ft•lb)

5-28
 CLUTCH

CLUTCH
REMOVING THE CLUTCH

Order Part name Q'ty Remarks

Refer to "CHANGING THE ENGINE OIL"
Drain the engine oil.
section in the CHAPTER 3.
Brake pedal Refer to "ENGINE REMOVAL" section.
Clutch cable Disconnect at engine side.
1 Clutch cover 1
2 Clutch spring 5
3 Pressure plate 1
4 Push rod 1 1
5 Circlip 1
6 Washer 1
7 Bearing 1
8 Ball 1
9 Push rod 2 1
10 Friction plate 9
11 Clutch plate 8
12 Cushion spring 1
13 Seat plate 1

5-29
 CLUTCH

Order Part name Q'ty Remarks

14 Nut (clutch boss) 1 Refer to removal section.
15 Lock washer 1 Refer to removal section.
16 Clutch boss 1 Refer to removal section.
17 Thrust washer 1
18 Primary driven gear 1
19 Push lever shaft 1

5-30
 CLUTCH

REMOVING THE CLUTCH BOSS CHECKING THE CLUTCH CHECKING THE PUSH LEVER
1. Remove: SPRINGS SHAFT
• Nut "1" 1. Measure: 1. Inspect:
• Lock washer "2" • Clutch spring free length "a" • Push lever shaft "1"
• Clutch boss "3" Out of specification → Replace Wear/damage → Replace.
springs as a set.
Straighten the lock washer tab and Clutch spring free
use the clutch holding tool "4" to hold length:
the clutch boss. 37.0 mm (1.46 in)
<Limit>: 36.0 mm (1.42
Clutch holding tool: in)
YM-91042/90890-04086
CHECKING THE PUSH ROD
1. Inspect:
• Push rod 1 "1"
• Bearing "2"
• Washer "3"
• Push rod 2 "4"
• Ball "5"
CHECKING THE FRICTION Wear/damage/bend → Replace.
PLATES
1. Measure:
• Friction plate thickness
Out of specification → Replace
friction plate as a set.
Measure at all four points.
Friction plate thickness:
2.9–3.1 mm (0.114–
A. For USA and CDN 0.122 in) INSTALLING THE PUSH LEVER
B. Except for USA and CDN <Limit>: 2.7 mm (0.106 SHAFT
CHECKING THE CLUTCH in) 1. Install:
HOUSING AND BOSS • Push lever shaft "1"
1. Inspect: • Bolt (push lever shaft) "2"
• Clutch housing "1" Bolt (push lever shaft):
Cracks/wear/damage → Replace. 10 Nm (1.0 m•kg, 7.2
• Clutch boss "2" ft•lb)
Scoring/wear/damage→Replace.

• Apply the lithium soap base grease

on the oil seal lip.
CHECKING THE CLUTCH PLATES • Apply the engine oil on the push le-
1. Measure: ver shaft.
• Clutch plate warpage • Fit the seat plate "3" in the groove
Out of specification → Replace "a" of the push lever shaft and tight-
clutch plate as a set. en the bolt (seat plate).
Use a surface plate "1" and thick-
CHECKING THE PRIMARY DRIVEN
ness gauge "2".
GEAR
1. Check: Warp limit:
• Circumferential play 0.1 mm (0.004 in)
Free play exists → Replace.
• Gear teeth "a"
Wear/damage → Replace.

5-31
 CLUTCH

INSTALLING THE CLUTCH

1. Install: • Install the seat plate with its cham-
• Primary driven gear "1" fered portion "a" facing the clutch
• Thrust washer "2" boss "3".
• Clutch boss "3" • Install the seat plate so that it is not
caught on the step "b".
Apply the engine oil on the primary • Install the cushion spring with the
driven gear inner circumference. paint "c" facing out.
7. Install:
• Push rod 2 "1"
• Ball "2"
• Push rod 1 "3"

Apply the engine oil on the push rod

1, 2 and ball.

2. Install: 5. Install:
• Lock washer "1" • Friction plate 1 "1"
• Nut (clutch boss) "2" • Clutch plate 1 "2"
Nut (clutch boss): • Friction plate 2 "3"
75 Nm (7.5 m•kg, 54 • Clutch plate 2 "4"
ft•lb)
• Install the clutch plates and friction
plates alternately on the clutch 8. Install:
Use the clutch holding tool "3" to hold boss, starting with a friction plate • Pressure plate "1"
the clutch boss. and ending with a friction plate.
• Use the friction plates 1 for the first
Clutch holding tool: and final while paying attention to
YM-91042/90890-04086 the difference in surface pattern.
• Apply the engine oil on the friction
plates and clutch plates.
• Unlike the clutch plate 2, the clutch
plate 1 has no surface gloss. Use
the clutch plate 1 for the first while 9. Install:
paying attention to the difference in • Clutch spring "1"
surface gloss. • Bolt (clutch spring) "2"
Bolt (clutch spring):
10 Nm (1.0 m•kg, 7.2
ft•lb)

Tighten the bolts in stage, using a

crisscross pattern.

A. For USA and CDN

B. Except for USA and CDN
3. Bend the lock washer "1" tab.

6. Install:
• Bearing "1"
• Washer "2"
• Circlip "3"
4. Install: To push rod 1 "4".
• Seat plate "1"
• Cushion spring "2" Apply the engine oil on the bearing
and washer.

5-32
 CLUTCH

10. Install:
• Dowel pin "1"
• Gasket (clutch cover) "2"

11. Install:
• Clutch cover "1"
• Bolt (clutch cover)
Bolt (clutch cover):
10 Nm (1.0 m•kg, 7.2
ft•lb)

Tighten the bolts in stage, using a

crisscross pattern.

5-33
 OIL FILTER ELEMENT AND WATER PUMP

OIL FILTER ELEMENT AND WATER PUMP

REMOVING THE OIL FILTER ELEMENT AND WATER PUMP

Order Part name Q'ty Remarks

Refer to "CHANGING THE ENGINE OIL"
Drain the engine oil.
section in the CHAPTER 3.
Refer to "CHANGING THE COOLANT" sec-
Drain the coolant.
tion in the CHAPTER 3.
Radiator hose 3 Disconnect at water pump side.
Refer to "REMOVING THE EXHAUST PIPE
Exhaust pipe
AND SILENCER" section in the CHAPTER 3.
Brake pedal Refer to "ENGINE REMOVAL" section.
Engine guard
1 Oil filter element cover 1
2 Oil filter element 1
3 Water pump housing 1
4 Oil delivery pipe 1
5 Bolt (oil hose) 1
6 Kickstarter crank 1
7 Right crankcase cover 1
8 Impeller 1 Refer to removal section.

5-34
 OIL FILTER ELEMENT AND WATER PUMP

Order Part name Q'ty Remarks

9 Washer 1 Refer to removal section.
10 Impeller shaft 1 Refer to removal section.
11 Oil seal 2 Refer to removal section.
12 Bearing 1 Refer to removal section.

5-35
 OIL FILTER ELEMENT AND WATER PUMP

REMOVING THE IMPELLER INSTALLING THE OIL SEAL

SHAFT 1. Install:
1. Remove: • Oil seal "1"
• Impeller "1"
• Washer "2" • Apply the lithium soap base grease
• Impeller shaft "3" on the oil seal lip.
• Install the oil seal with its manufac-
Hold the impeller shaft on its width ture's marks or numbers facing the
across the flats "a" with spanners, CHECKING THE IMPELLER SHAFT right crankcase cover "2".
etc. and remove the impeller. 1. Inspect:
• Impeller shaft "1"
Bend/wear/damage → Replace.
Fur deposits → Clean.

2. Install:
• Bearing "1"

CHECKING THE IMPELLER SHAFT Install the bearing by pressing its out-
GEAR er race parallel.
1. Inspect:
• Gear teeth "a"
Wear/damage → Replace.

REMOVING THE OIL SEAL

It is not necessary to disassemble the

water pump, unless there is an abnor-
mality such as excessive change in
coolant level, discoloration of coolant, INSTALLING THE IMPELLER
or milky transmission oil. SHAFT
CHECKING THE BEARING 1. Install:
1. Remove: 1. Inspect: • Impeller shaft "1"
• Bearing "1" • Bearing • Washer "2"
Rotate inner race with a finger. • Impeller "3"
Rough spot/seizure → Replace. Impeller:
14 Nm (1.4 m•kg, 10
ft•lb)

• Take care so that the oil seal lip is

not damaged or the spring does not
2. Remove: slip off its position.
• Oil seal "1" • When installing the impeller shaft,
CHECKING THE OIL SEAL apply the lithium soap base grease
1. Inspect: on the oil seal lip and impeller shaft.
• Oil seal "1" And install the shaft while turning it.
Wear/damage → Replace. • Hold the impeller shaft on its width
across the flats "a" with spanners,
etc. and install the impeller.

CHECKING THE OIL DELIVERY

PIPE
1. Inspect:
• Oil delivery pipe "1"
Bend/damage → Replace.
Clogged → Blow.

5-36
 OIL FILTER ELEMENT AND WATER PUMP

INSTALLING THE KICKSTARTER

CRANK
1. Install:
• Kickstarter crank "1"
• Washer
• Bolt (kickstarter crank)
Bolt (kickstarter crank):
33 Nm (3.3 m•kg, 24
INSTALLING THE RIGHT ft•lb) INSTALLING THE WATER PUMP
CRANKCASE COVER HOUSING
1. Install: 1. Install:
• Dowel pin "1" Install so that there is a clearance "a" • Dowel pin "1"
• O-ring "2" of 13 mm (0.51 in) or more between • O-ring "2"
• Collar "3" the kickstarter and frame and that the
• Gasket "4" kickstarter does not contact the Apply the lithium soap base grease
crankcase cover when it is pulled. on the O-ring.
Apply the lithium soap base grease
on the O-ring.

2. Install: 2. Install:
• Oil hose "1" • Water pump housing "1"
2. Install: • Bolt (oil hose) "2" • Bolt (water pump housing) "2"
• Right crankcase cover "1" Bolt (oil hose): Bolt (water pump hous-
• Bolt (right crankcase cover) "2" 8 Nm (0.8 m•kg, 5.8 ing):
Bolt (right crankcase ft•lb) 10 Nm (1.0 m•kg, 7.2
cover): ft•lb)
10 Nm (1.0 m•kg, 7.2
ft•lb)

• Apply the engine oil on the impeller

shaft end.
• Mesh the impeller shaft gear "3"
with primary drive gear "4".
• Tighten the bolts in stage, using a 3. Install:
crisscross pattern. • Copper washer "1"
• Oil delivery pipe "2"
• Union bolt (M8) "3"
Union bolt (M8):
18 Nm (1.8 m•kg, 13
ft•lb)
• Union bolt (M10) "4"
Union bolt (M10):
20 Nm (2.0 m•kg, 14
ft•lb)

First tighten the union bolts temporar-

ily. Then retighten them with the width
"a" across flats of the oil delivery pipe
held tight with a spanner.

5-37
 OIL FILTER ELEMENT AND WATER PUMP

INSTALLING THE OIL FILTER

ELEMENT
1. Install:
• Oil filter element "1"
• O-ring "2"
• Oil filter element cover "3"
• Bolt (oil filter element cover)
Bolt (oil filter element
cover):
10 Nm (1.0 m•kg, 7.2
ft•lb)

Apply the lithium soap base grease

on the O-ring.

5-38
 BALANCER

BALANCER
REMOVING THE BALANCER

Order Part name Q'ty Remarks

Primary driven gear Refer to "CLUTCH" section.
Refer to "OIL FILTER ELEMENT AND WA-
Right crankcase cover
TER PUMP" section.
Refer to "AC MAGNETO AND STARTER
Stator
CLUTCH" section.
1 Nut (primary drive gear) 1 Refer to removal section.
2 Nut (balancer shaft driven gear) 1 Refer to removal section.
3 Lock washer 1
4 Primary drive gear 1
5 Balancer shaft drive gear 1
6 Lock washer 1
7 Balancer shaft driven gear 1
8 Balancer shaft 1 Refer to removal section.

5-39
 BALANCER

REMOVING THE BALANCER CHECKING THE BALANCER

1. Straighten the lock washer tab. SHAFT
2. Loosen: 1. Inspect:
• Nut (primary drive gear) "1" • Balancer shaft
• Nut (balancer shaft driven gear) Cracks/damage → Replace.
"2"

Place an aluminum plate "a" between

the teeth of the balancer shaft drive 4. Install:
gear "3" and driven gear "4". • Lock washer "1"
• Nut (balancer shaft driven gear)
"2"
Nut (balancer shaft driv-
INSTALLING THE BALANCER en gear):
1. Install: 50 Nm (5.0 m•kg, 36
• Balancer shaft "1" ft•lb)

• Apply the engine oil on the bearing. • Primary drive gear "3"
• When installing the balancer shaft, • Lock washer "4"
align the center "a" of the balancer • Nut (primary drive gear) "5"
shaft weight along the line connect- Nut (primary drive gear):
ing the centers of the crankshaft 75 Nm (7.5 m•kg, 54
and balancer shaft. ft•lb)

• Install the primary drive gear with its

stepped side "a" facing the engine.
3. Remove: • Place an aluminum plate "b" be-
• Balancer shaft "1" tween the teeth of the balancer
shaft drive gear "6" and driven gear
When removing the balancer shaft, "7".
align the center "a" of the balancer
shaft weight along the line connecting 2. Install:
the centers of the crankshaft and bal- • Balancer shaft driven gear "1"
ancer shaft.
Install the balancer shaft driven gear
onto the balancer shaft while aligning
the punch mark "a" on the balancer
shaft driven gear with the lower spline
"b" on the balancer shaft end.

CHECKING THE PRIMARY DRIVE

GEAR, BALANCER SHAFT DRIVE
GEAR AND BALANCER SHAFT
DRIVEN GEAR
1. Inspect: 5. Bend the lock washer tab.
• Primary drive gear "1" 3. Install:
• Balancer shaft drive gear "2" • Balancer shaft drive gear "1"
• Balancer shaft driven gear "3"
Wear/damage → Replace. • Align the punched mark "a" on the
balancer shaft drive gear with the
punched mark "b" on the balancer
shaft driven gear "2".
• Align the punched mark "c" on the
balancer shaft drive gear with the
lower spline "d" on the crankshaft
end.

5-40
 OIL PUMP

OIL PUMP
REMOVING THE OIL PUMP

Order Part name Q'ty Remarks

Primary driven gear Refer to "CLUTCH" section.
Refer to "OIL FILTER ELEMENT AND WA-
Right crankcase cover
TER PUMP" section.
1 Circlip 1
2 Washer 1
3 Oil pump drive gear 1
4 Oil pump assembly 1
5 Outer rotor 2 1
6 Circlip 1
7 Inner rotor 2 1
8 Dowel pin 1
9 Oil pump cover 1
10 Outer rotor 1 1
11 Inner rotor 1 1
12 Dowel pin 1
13 Washer 1
14 Oil pump drive shaft 1
15 Rotor housing 1

5-41
 OIL PUMP

REMOVING THE OIL TANK

Order Part name Q'ty Remarks

Refer to "CHANGING THE ENGINE OIL"
Drain the engine oil.
section in the CHAPTER 3.
1 Oil hose 2 1
2 Oil hose 1 1
3 Dowel pin 2
4 Oil tank breather hose 1
5 Oil tank 1
6 Oil strainer 1

5-42
 OIL PUMP

CHECKING THE OIL PUMP 3. Check:

1. Inspect: • Unsmooth→Repeat steps #1 and
• Oil pump drive gear "1" #2 or replace the defective parts.
• Oil pump drive shaft "2"
• Rotor housing "3"
• Oil pump cover "4"
Cracks/wear/damage → Replace.

4. Install:
• Outer rotor 2 "1"
• Dowel pin "2"
INSTALLING THE OIL PUMP • Oil pump assembly "3"
1. Install: • Bolt (oil pump assembly)
• Oil pump drive shaft "1" [L = 25 mm (0.94 in)] "4"
• Washer "2" Bolt (oil pump assem-
2. Measure: • Dowel pin "3" bly):
• Tip clearance "a" • Inner rotor 1 "4" 10 Nm (1.0 m•kg, 7.2
(between the inner rotor "1" and ft•lb)
outer rotor "2") • Apply the engine oil on the oil pump
• Side clearance "b" drive shaft and inner rotor 1. • Bolt (oil pump assembly)
(between the outer rotor "2" and • Fit the dowel pin into the groove in [L = 30 mm (1.18 in)] "5"
rotor housing "3") the inner rotor 1. Bolt (oil pump assem-
• Housing and rotor clearance "c" bly):
(between the rotor housing "3" 10 Nm (1.0 m•kg, 7.2
and rotors "1" "2") ft•lb)
Out of specification→Replace the
oil pump assembly.
Tip clearance "a": Apply the engine oil on the outer rotor
0.12 mm or less (0.0047 2.
in or less)
<Limit>: 0.20 mm
2. Install:
(0.008 in)
• Outer rotor 1 "1"
Side clearance "b":
0.09–0.17 mm (0.0035–
0.0067 in) Apply the engine oil on the outer rotor
<Limit>: 0.24 mm 1.
(0.009 in)
Housing and rotor clear- 5. Install:
ance "c": • Oil pump drive gear "1"
0.03–0.10 mm (0.0012– • Washer "2"
0.0039 in) • Circlip "3"
<Limit>: 0.17 mm
(0.0067 in)
Apply the engine oil on the oil pump
drive gear inner circumference.
3. Install:
• Oil pump cover "1"
• Screw (oil pump cover) "2"
Screw (oil pump cover):
1.7 Nm (0.17 m•kg, 1.2
ft•lb)
• Dowel pin "3"
• Inner rotor 2 "4"
• Circlip "5"

• Apply the engine oil on the inner ro-

tor 2.
• Fit the dowel pin into the groove in
the inner rotor 2.

5-43
 KICK SHAFT AND SHIFT SHAFT

KICK SHAFT AND SHIFT SHAFT

REMOVING THE KICK SHAFT AND SHIFT SHAFT

Order Part name Q'ty Remarks

Oil pump Refer to "OIL PUMP" section.
1 Kick idle gear 1
2 Kick shaft assembly 1 Refer to removal section.
3 Spring guide 1
4 Torsion spring 1
5 Ratchet wheel 1
6 Kick gear 1
7 Kick shaft 1
8 Washer 1
9 Shift pedal 1
10 Shift shaft 1
11 Collar 1
12 Torsion spring 1
13 Roller 1
14 Shift guide 1 Refer to removal section.
15 Shift lever assembly 1 Refer to removal section.
16 Shift lever 1

5-44
 KICK SHAFT AND SHIFT SHAFT

Order Part name Q'ty Remarks

17 Pawl 2
18 Pawl pin 2
19 Spring 2
20 Bolt (stopper lever) 1
21 Stopper lever 1
22 Torsion spring 1
23 Segment 1 Refer to removal section.

5-45
 KICK SHAFT AND SHIFT SHAFT

REMOVING THE KICK SHAFT CHECKING THE KICK SHAFT AND CHECKING THE SHIFT GUIDE AND
ASSEMBLY RATCHET WHEEL SHIFT LEVER ASSEMBLY
1. Remove: 1. Check: 1. Inspect:
• Kick shaft assembly "1" • Ratchet wheel "1" smooth move- • Shift guide "1"
ment • Shift lever "2"
Unhook the torsion spring "2" from Unsmooth movement → Replace. • Pawl "3"
the hole "a" in the crankcase. • Kick shaft "2" • Pawl pin "4"
Wear/damage → Replace. • Spring "5"
• Spring "3" Wear/damage → Replace.
Broken → Replace.

REMOVING THE SHIFT GUIDE

AND SHIFT LEVER ASSEMBLY CHECKING THE STOPPER LEVER
1. Remove: CHECKING THE KICK GEAR, KICK 1. Inspect:
• Bolt (shift guide) IDLE GEAR AND RATCHET • Stopper lever "1"
• Shift guide "1" WHEEL Wear/damage → Replace.
• Shift lever assembly "2" 1. Inspect: • Torsion spring "2"
• Kick gear "1" Broken → Replace.
The shift lever assembly is disassem- • Kick idle gear "2"
bled at the same time as the shift • Ratchet wheel "3"
guide. • Gear teeth "a"
• Ratchet teeth "b"
Wear/damage → Replace.

INSTALLING THE SEGMENT

1. Install:
• Segment "1"
• Bolt (segment)
REMOVING THE SEGMENT
1. Remove: Bolt (segment):
CHECKING THE SHIFT SHAFT 30 Nm (3.0 m•kg, 22
• Bolt (segment) "1" 1. Inspect:
• Segment "2" ft•lb)
• Shift shaft "1"
Bend/damage → Replace.
Turn the segment counterclockwise • Spring "2" Align the notch "a" on the segment
until it stops and loosen the bolt. Broken → Replace. with the pin "b" on the shift cam.

If the segment gets an impact, it If the segment gets an impact, it

may be damaged. Take care not to may be damaged. Take care not to
give an impact to the segment give an impact to the segment
when removing the bolt. when tightening the bolt.

5-46
 KICK SHAFT AND SHIFT SHAFT

INSTALLING THE STOPPER 3. Install: INSTALLING THE KICK SHAFT

LEVER • Shift lever assembly "1" ASSEMBLY
1. Install: • Shift guide "2" 1. Install:
• Torsion spring "1" • Kick gear "1"
• Stopper lever "2" • The shift lever assembly is installed • Washer "2"
• Bolt (stopper lever) "3" at the same time as the shift guide. • Circlip "3"
Bolt (stopper lever): • Apply the engine oil on the bolt • Ratchet wheel "4"
10 Nm (1.0 m•kg, 7.2 (segment) shaft. • Spring "5"
ft•lb) • Washer "6"
• Circlip "7"
To kick shaft "8".
Align the stopper lever roller with the
slot on segment. • Apply the molybdenum disulfide oil
on the inner circumferences of the
kick gear and ratchet wheel.
• Align the punch mark "a" on the
ratchet wheel with the punch mark
4. Install: "b" on the kick shaft.
• Bolt (shift guide) "1"
Bolt (shift guide):
10 Nm (1.0 m•kg, 7.2
ft•lb)
INSTALLING THE SHIFT GUIDE
AND SHIFT LEVER ASSEMBLY
1. Install:
• Spring "1"
• Pawl pin "2"
• Pawl "3" 2. Install:
To shift lever "4". • Torsion spring "1"
To kick shaft "2".
Apply the engine oil on the spring,
pawl pin and pawl. INSTALLING THE SHIFT SHAFT Make sure the stopper "a" of the tor-
1. Install: sion spring fits into the hole "b" on the
• Roller "1" kick shaft.
• Collar "2"
• Torsion spring "3"
• Shift shaft "4"

Apply the engine oil on the roller and

shift shaft.

2. Install:
• Shift lever assembly "1"
To shift guide "2". 3. Install:
• Spring guide "1"

Slide the spring guide into the kick

shaft, make sure the groove "a" in the
spring guide fits on the stopper of the
2. Install: torsion spring.
• Shift pedal
Refer to "AC MAGNETO AND
STARTER CLUTCH" section.

5-47
 KICK SHAFT AND SHIFT SHAFT

4. Install:
• Kick shaft assembly "1"
• Washer "2"

• Apply the molybdenum disulfide

grease on the contacting surfaces
of the kick shaft stopper "a" and kick
shaft ratchet wheel guide "3".
• Apply the engine oil on the kick
shaft.
• Slide the kick shaft assembly into
the crankcase and make sure the
kick shaft stopper "a" fits into the
kick shaft ratchet wheel guide.

5. Hook:
• Torsion spring "1"

Turn the torsion spring clockwise and

hook into the proper hole "a" in the
crankcase.

INSTALLING THE KICK IDLE

GEAR
1. Install:
• Kick idle gear "1"
• Washer "2"
• Circlip "3"

• Apply the engine oil on the kick idle

gear inner circumference.
• Install the kick idle gear with its de-
pressed side "a" toward you.

5-48
 AC MAGNETO AND STARTER CLUTCH

AC MAGNETO AND STARTER CLUTCH

REMOVING THE AC MAGNETO AND STARTER CLUTCH

Order Part name Q'ty Remarks

Refer to "CHANGING THE ENGINE OIL"
Drain the engine oil.
section in the CHAPTER 3.
Refer to "REMOVING THE SEAT, FUEL
Seat and fuel tank TANK AND SIDE COVERS" section in the
CHAPTER 3.
Disconnect the AC magneto lead.
1 Shift pedal 1
2 Cover (torque limiter) 1
3 Torque limiter 1 Do not disassemble.
4 Crankcase cover (left) 1
5 Gasket 1
6 Dowel pin 2
7* Nut (rotor) 1 Refer to TIP.
8 Rotor 1 Refer to removal section.
9 Woodruff key 1
10 Starter clutch drive gear 1
11 Starter clutch assembly cover 1

5-49
 AC MAGNETO AND STARTER CLUTCH

Order Part name Q'ty Remarks

12 Starter clutch 1 Refer to removal section.
13 Bearing 1
14 Washer 1
15 Idle gear plate 1
16 Idle gear 1
17 Holder 1
18 Pickup coil 1
19 Stator 1

Tighten the rotor nut to 65 Nm (6.5 m•kg, 47 ft•lb), loosen and retighten the rotor nut to 65 Nm (6.5 m•kg, 47 ft•lb).

5-50
 AC MAGNETO AND STARTER CLUTCH

REMOVING THE ROTOR 3. Check:

1. Remove: • Starter clutch operation
• Nut (rotor) "1"
• Washer a. Install the starter clutch drive gear
Use the sheave holder "2". "1" onto the starter clutch "2" and
Sheave holder: hold the starter clutch.
YS-1880-A/90890- b. When turning the starter clutch
01701 drive gear counterclockwise "B",
CHECKING THE AC MAGNETO the starter clutch and the starter
1. Inspect: clutch drive gear should engage.
• Rotor inner surface "a" If the starter clutch drive gear and
• Stator outer surface "b" starter clutch do not engage, the
Damage→ Inspect the crankshaft starter clutch is faulty and must be
runout and crankshaft bearing. replaced.
If necessary, replace AC magneto c. When turning the starter clutch
and/or stator. drive gear clockwise "A", it should
turn freely. If the starter clutch
2. Remove:
drive gear does not turn freely, the
• Rotor "1"
starter clutch is faulty and must be
Use the rotor puller "2".
replaced.
Rotor puller:
YM-04141/90890-04141

CHECKING THE WOODRUFF KEY

1. Inspect:
• Woodruff key "1"
Damage → Replace.

CHECKING THE TORQUE LIMITER

REMOVING THE STARTER 1. Check:
CLUTCH • Torque limiter
1. Remove: Damage/wear → Replace.
• Starter clutch assembly cover "1"

Insert a thin screwdriver or the like CHECKING THE STARTER

under the convexity "a" and remove CLUTCH
the starter clutch assembly cover by 1. Check:
prying it gently to void damage to the • Starter clutch
cover. Damage/wear → Replace.
2. Check:
• Idle gear INSTALLING THE AC MAGNETO
• Starter clutch drive gear AND STARTER CLUTCH
Pitting/burrs/chips/roughness/ 1. Install:
wear → Replace the defective • Stator "1"
parts. • Bolt (stator) "2"
Bolt (stator):
7 Nm (0.7 m•kg, 5.1
ft•lb)
2. Remove:
• Starter clutch "1"

Using a thin screwdriver or the like,

remove the plate "a" while prying it
upward little by little.

5-51
 AC MAGNETO AND STARTER CLUTCH

• Pickup coil "3" 4. Install:

• Bolt (pickup coil) "4" • Idle gear plate "1"
Bolt (pickup coil): • Bolt (idle gear plate) "2"
10 Nm (1.0 m•kg, 7.2 Bolt (idle gear plate):
ft•lb) 10 Nm (1.0 m•kg, 7.2
ft•lb)

8. Install:
• Woodruff key "1"
• Rotor "2"

• Degrease the contact surfaces of

the tapered portions of the crank-
2. Install: shaft and rotor.
• Holder "1" 5. Install: • When installing the woodruff key,
• Bolt "2" • Washer "1" make sure that its flat surface "a" is
Bolt: • Bearing "2" in parallel with the crankshaft center
7 Nm (0.7 m•kg, 5.1 • Starter clutch drive gear "3" line "b".
ft•lb) • Washer "4" • When installing the rotor, align the
keyway "c" of the rotor with the
Apply the engine oil on the washer, woodruff key.
Pass the pickup coil lead and bearing and starter clutch drive gear
charging coil lead under the holder inner circumference.
while taking care not to allow these
leads to get caught with each oth-
er. Also take care to pass the leads
so that they do not become loose E

at the bend of the holder "a" in or-

der to avoid their contacting the
starter clutch drive gear. 9. Install:
• Washer (rotor)
6. Install: • Nut (rotor) "1"
Apply the sealant to the grommet of
• Starter clutch "1"
the AC magneto lead. Nut (rotor):
To rotor "2".
65 Nm (6.5 m•kg, 47
YAMAHA Bond No. 1215 ft•lb)
• Install the starter clutch with its
(ThreeBond® No. 1215): Use the sheave holder "2"
plate side upward.
90890-85505
• While installing the starter clutch,
push in the projections "a" one by Tighten the rotor nut to 65 Nm (6.5
one on the clutch circumference. m•kg, 47 ft•lb), loosen and retighten
• Push in the starter clutch until it hits the rotor nut to 65 Nm (6.5 m•kg, 47
the rotor. ft•lb).

Sheave holder:
YS-1880-A/90890-
01701
3. Install:
• Idle gear 2 "1"
• Dowel pin "2"

Apply the engine oil on the idle gear

7. Install:
2.
• Starter clutch assembly cover "1"
To rotor "2".

Install the starter clutch assembly

cover by fitting its pawls "a" into the
groove "b" in the rotor.

5-52
 AC MAGNETO AND STARTER CLUTCH

10. Install:
• Dowel pin
• Gasket [crankcase cover (left)]

• Crankcase cover (left) "1"

• Bolt [crankcase cover (left)] "2"
Bolt [crankcase cover
(left)]:
10 Nm (1.0 m•kg, 7.2 13. Connect:
ft•lb) • AC magneto lead
Refer to "CABLE ROUTING DIA-
• Bolt [crankcase cover (left)] "3" GRAM" section in the CHAPTER
Bolt [crankcase cover 2.
(left)]:
12 Nm (1.2 m•kg, 8.7
ft•lb)

Tighten the bolts in stage, using a

crisscross pattern.

14. Install:
• Shift pedal "1"
• Bolt (shift pedal) "2"
Bolt (shift pedal):
12 Nm (1.2 m•kg, 8.7
ft•lb)

11. Install:
When installing the shift pedal onto
• Washer "1"
the shift shaft, be sure that the center
• Torque limiter "2"
of the shift pedal is about 1.4 mm
• Washer "3"
(0.06 in) "a" above the top of the foot-
rest.
Apply the engine oil to the shaft and
washers.

12. Install:
• O-ring
• Cover (idle gear 1) "1"
• Bolt "2"
Bolt:
10 Nm (1.0 m•kg, 7.2
ft•lb)

• Apply the lithium soap base grease

on the O-ring.
• Install the cover (idle gear 1) with its
mark "a" facing upward.

5-53
 ENGINE REMOVAL

ENGINE REMOVAL
REMOVING THE ENGINE

Order Part name Q'ty Remarks

Hold the machine by placing the suitable stand
Refer to "HANDLING NOTE".
under the frame.
Refer to "CHANGING THE ENGINE OIL"
Drain the engine oil.
section in the CHAPTER 3.
Refer to "REMOVING THE SEAT, FUEL
Seat and fuel tank TANK AND SIDE COVERS" section in the
CHAPTER 3.
Carburetor Refer to "CARBURETOR" section.
Refer to "REMOVING THE EXHAUST PIPE
Exhaust pipe and silencer
AND SILENCER" section in the CHAPTER 3.
Air cut-off valve assembly Refer to "AIR INDUCTION SYSTEM" section.
Clutch cable Disconnect at the engine side.
Radiator Refer to "RADIATOR" section.
Refer to "AC MAGNETO AND STARTER
Shift pedal
CLUTCH" section.
Cylinder head breather hose Refer to "CAMSHAFTS" section.
Oil hose and oil tank breather hose Refer to "OIL PUMP" section.
Ignition coil

5-54
 ENGINE REMOVAL

Order Part name Q'ty Remarks

Disconnect the AC magneto lead.
Negative battery lead Disconnect at the engine side.
1 Engine guard 1
2 Neutral switch 1
3 Drive chain sprocket cover 1
4 Nut (drive sprocket) 1 Refer to removal section.
5 Lock washer 1 Refer to removal section.
6 Drive sprocket 1 Refer to removal section.
7 Clip 1
8 Bolt (brake pedal) 1
9 Brake pedal 1
10 Upper engine bracket 2
11 Lower engine bracket 2
12 Engine mounting bolt 3
13 Pivot shaft 1 Refer to removal section.
14 Engine 1 Refer to removal section.

5-55
 ENGINE REMOVAL

HANDLING NOTE 2. Remove:

• Engine "1" • Apply the molybdenum disulfide
From right side. grease on the pivot shaft.
Support the machine securely so
• Install the patch with the claw "a"
there is no danger of it falling over.
Make sure that the couplers, hoses facing outside the chassis.
REMOVING THE DRIVE and cables are disconnected.
SPROCKET
1. Remove:
• Nut (drive sprocket) "1"
• Lock washer "2"

• Straighten the lock washer tab.

• Loosen the nut while applying the
rear brake.
INSTALLING THE ENGINE
1. Install:
• Engine "1"
Install the engine from right side.
• Pivot shaft "2"
Pivot shaft:
85 Nm (8.5 m•kg, 61 INSTALLING THE BRAKE PEDAL
ft•lb) 1. Install:
2. Remove: • Spring "1"
• Engine mounting bolt (lower) "3"
• Drive sprocket "1" • Brake pedal "2"
• Drive chain "2" Engine mounting bolt • O-ring "3"
(lower): • Bolt (brake pedal) "4"
Remove the drive sprocket together 53Nm (5.3 m•kg, 38
ft•lb) Bolt (brake pedal):
with the drive chain. 26 Nm (2.6 m•kg, 19
• Lower engine bracket "4" ft•lb)
• Bolt (lower engine bracket) "5"
• Clip "5"
Bolt (lower engine brack-
et):
Apply the lithium soap base grease
34 Nm (3.4 m•kg, 24
on the bolt, O-rings and brake pedal
ft•lb)
bracket.
• Patch "6"
• Engine mounting bolt (front) "7"
REMOVING THE ENGINE
1. Remove: Engine mounting bolt
• Pivot shaft "1" (front):
53 Nm (5.3 m•kg, 38
ft•lb)
If the pivot shaft is pulled all the way
out, the swingarm will come loose. If • Upper engine bracket "8"
possible, insert a shaft of similar di- • Bolt (upper engine bracket) "9"
ameter into the other side of the INSTALLING THE DRIVE
Bolt (upper engine brack- SPROCKET
swingarm to support it.
et): 1. Install:
34 Nm (3.4 m•kg, 24 • Drive sprocket "1"
ft•lb) • Drive chain "2"
• Engine mounting bolt (upper) "10"
Install the drive sprocket together
Engine mounting bolt
with the drive chain.
(upper):
55 Nm (5.5 m•kg, 40
ft•lb)
• Lower engine guard "11"
• Bolt (lower engine guard) "12"
Bolt (lower engine
guard):
7 Nm (0.7 m•kg, 5.1
ft•lb)

5-56
 ENGINE REMOVAL

2. Install:
• Lock washer "1"
• Nut (drive sprocket) "2"
Nut (drive sprocket):
75 Nm (7.5 m•kg, 54
ft•lb)

Tighten the nut while applying the

rear brake.

3. Bend the lock washer tab to lock

the nut.
4. Install:
• Drive chain sprocket guide "1"
• Drive chain sprocket cover "2"
• Bolt (drive chain sprocket cover)
"3"
Bolt (drive chain sprock-
et cover):
7 Nm (0.7 m•kg, 5.1
ft•lb)

INSTALLING THE NEUTRAL

SWITCH
1. Install:
• Spring "1"
• Pin "2"
• O-ring "3"
• Neutral switch "4"
• Screw (neutral switch) "5"
Screw (neutral switch):
4 Nm (0.4 m•kg, 2.9
ft•lb)

Apply the lithium soap base grease

on the O-ring.

5-57
 CRANKCASE AND CRANKSHAFT

CRANKCASE AND CRANKSHAFT

REMOVING THE CRANKSHAFT

Order Part name Q'ty Remarks

Engie Refer to "ENGINE REMOVAL" section.
Piston Refer to "CYLINDER AND PISTON" section.
Refer to "KICK SHAFT AND SHIFT SHAFT"
Kick shaft assembly
section.
Refer to "KICK SHAFT AND SHIFT SHAFT"
Segment
section.
Refer to "AC MAGNETO AND STARTER
Stator
CLUTCH" section.
Balancer shaft Refer to "BALANCER" section.
1 Timing chain guide (intake side) 1
2 Timing chain 1
3 Oil delivery pipe 2 1
4 Bolt [L = 45 mm (1.77 in)] 5 Refer to removal section.
5 Bolt [L = 55 mm (2.17 in)] 1 Refer to removal section.
6 Bolt [L = 70 mm (2.76 in)] 3 Refer to removal section.
7 Hose guide 1 Refer to removal section.
8 Clutch cable holder 1 Refer to removal section.

5-58
 CRANKCASE AND CRANKSHAFT

Order Part name Q'ty Remarks

9 Right crankcase 1 Refer to removal section.
10 Left crankcase 1 Refer to removal section.
11 Oil strainer 1
12 Crankshaft 1 Refer to removal section.

5-59
 CRANKCASE AND CRANKSHAFT

REMOVING THE CRANKCASE BEARING

Order Part name Q'ty Remarks

Refer to "TRANSMISSION, SHIFT CAM AND
Transmission
SHIFT FORK" section.
Refer to "TRANSMISSION, SHIFT CAM AND
Shift cam and shift fork
SHIFT FORK" section.
1 Oil seal 2
2 Bearing 10 Refer to removal section.

5-60
 CRANKCASE AND CRANKSHAFT

DISASSEMBLING THE c. Remove the dowel pins and O- CHECKING THE CRANKCASE
CRANKCASE ring. 1. Inspect:
1. Separate: • Contacting surface "a"
• Right crankcase Scratches → Replace.
REMOVING THE CRANKSHAFT
• Left crankcase • Engine mounting boss "b", crank-
1. Remove:
case
• Crankshaft "1"
Separation steps: Cracks/damage → Replace.
Use the crankcase separating
a. Remove the crankcase bolts "1", tool "2".
hose guide "2" and clutch cable
Crankcase separating
holder "3".
tool:
YU-1135-A/90890-
01135

Do not use a hammer to drive out 2. Inspect:

the crankshaft. • Bearing
Rotate inner race with a finger.
Rough spot/seizure → Replace.
Loosen each bolt 1/4 of a turn at a
time and after all the bolts are loos-
ened, remove them.

b. Remove the right crankcase "4".

• Place the crankcase with its left REMOVING THE CRANKCASE

side downward and split it by insert- BEARING
ing a screwdriver tip into the split- 3. Inspect:
1. Remove: • Oil seal
ting slit "a" in the crankcase. • Bearing "1"
• Lift the right crankcase horizontally Damage → Replace.
while lightly patting the case split- CHECKING THE CRANKSHAFT
• Remove the bearing from the 1. Measure:
ting slit and engine mounting boss
crankcase by pressing its inner • Runout limit "a"
using a soft hammer, and leave the
race. • Small end free play limit "b"
crankshaft and transmission with
• Do not use the removed bearing. • Connecting rod big end side
the left crankcase.
clearance "c"
• Crank width "d"
Out of specification → Replace.
Use soft hammer to tap on the
Use the dial gauge and a thick-
case half. Tap only on reinforced
ness gauge.
portions of case. Do not tap on
gasket mating surface. Work slow- Dial gauge and stand:
ly and carefully. Make sure the YU-3097/90890-01252
case halves separate evenly. If the
cases do not separate, check for a CHECKING THE TIMING CHAIN
AND TIMING CHAIN GUIDE Standard <Limit>
remaining case bolt or fitting. Do
not force. 1. Inspect:
• Timing chain 0.05
Run-
Cracks/stiff → Replace the timing 0.03 mm (0.0012 mm
out
chain and camshaft sprocket as a in) (0.002
limit:
set. in)
Small
end 0.4–1.0 mm 2.0 mm
free (0.016–0.039 in) (0.08 in)
play:
Side 0.15–0.45 mm 0.50
clear- (0.0059–0.0177 mm
ance: in) (0.02 in)
2. Inspect: 55.95–56.00
Crack
• Timing chain guide mm (2.203– —
width:
Wear/damage → Replace. 2.205 in)

5-61
 CRANKCASE AND CRANKSHAFT

• Screw [bearing stopper (crank-

shaft)] "1"
Screw [bearing stopper
(crankshaft)]:
14 Nm (1.4 m•kg, 10
ft•lb)
To left and right crankcase.

• Install the bearing by pressing its

outer race parallel.
• To prevent the screw [bearing stop-
per (crankshaft)] from becoming
loose, crush the screw head periph-
ery "a" into the concave "b" using a
punch etc. In so doing, take care
CHECKING THE OIL STRAINER not to damage the screwdriver re- A. For USA and CDN
1. Inspect: ceiving hole in the screw head. B. Except for USA and CDN
• Oil strainer 2. Check:
Damage → Replace. • Shifter operation
• Transmission operation
Unsmooth operation → Repair.

INSTALLING THE CRANKSHAFT

CHECKING THE OIL DELIVERY 1. Install:
PIPE 2 • Crankshaft "1"
1. Inspect: Use the crankshaft installing tool 3. Install:
• Oil delivery pipe 2 "1" "2", "3", "4" and "5". • Oil strainer "1"
• O-ring "2" Crankshaft installing pot • Bolt (oil strainer) "2"
Damage → Replace. "2": Bolt (oil strainer):
• Oil orifice "a" YU-90050/90890-01274 10 Nm (1.0 m•kg, 7.2
Clogged → Blow. Crankshaft installing bolt ft•lb)
"3":
YU-90050/90890-01275
Adapter (M12) "4":
YU-90063/90890-01278
Spacer (crankshaft in-
staller) "5":
YU-91044/90890-04081

INSTALLING THE CRANKCASE

BEARING • Hold the connecting rod at top dead 4. Apply:
1. Install: center with one hand while turning • Sealant
• Bearing the nut of the installing tool with the On the right crankcase "1".
• Bearing stopper other. Operate the installing tool un- YAMAHA Bond No. 1215
• Bolt (bearing stopper) til the crankshaft bottoms against (ThreeBond® No.1215):
the bearing. 90890-85505
Bolt (bearing stopper):
• Before installing the crankshaft,
10 Nm (1.0 m•kg, 7.2
clean the contacting surface of
ft•lb)
crankcase. Clean the contacting surface of left
• Screw (bearing stopper) and right crankcase before applying
Screw (bearing stopper): the sealant.
10 Nm (1.0 m•kg, 7.2 Do not use a hammer to drive in
ft•lb) the crankshaft.

5-62
 CRANKCASE AND CRANKSHAFT

Apply the lithium soap base grease

on the Orings.

5. Install:
• Dowel pin "1"
• O-ring "2"
• Right crankcase
To left crankcase. 8. Install:
• Timing chain "1"
• Apply the lithium soap base grease • Timing chain guide (intake side)
on the O-ring. "2"
• Fit the right crankcase onto the left • Bolt (timing chain guide) "3"
crankcase. Tap lightly on the case Bolt (timing chain guide):
with soft hammer. 10 Nm (1.0 m•kg, 7.2
• When installing the crankcase, the ft•lb)
connecting rod should be posi-
tioned at TDC (top dead center).

9. Remove:
• Sealant
6. Tighten: Forced out on the cylinder mating
• Hose guide "1" surface.
• Clutch cable holder "2" 10. Apply:
• Bolt (crankcase) "3" • Engine oil
To the crank pin, bearing and oil
Bolt (crankcase):
delivery hole.
12 Nm (1.2 m•kg, 8.7
11. Check:
ft•lb)
• Crankshaft and transmission op-
eration.
Tighten the crankcase tightening Unsmooth operation → Repair.
bolts in stage, using a crisscross pat-
tern.

7. Install:
• Oil delivery pipe 2 "1"
• O-ring "2"
• Bolt (oil delivery pipe 2) "3"
Bolt (oil delivery pipe 2):
10 Nm (1.0 m•kg, 7.2
ft•lb)

5-63
 TRANSMISSION, SHIFT CAM AND SHIFT FORK

TRANSMISSION, SHIFT CAM AND SHIFT FORK

REMOVING THE TRANSMISSION, SHIFT CAM AND SHIFT FORK

Order Part name Q'ty Remarks

Engine Refer to "ENGINE REMOVAL" section.
Refer to "CRANKCASE AND CRANK-
Separate the crankcase.
SHAFT" section.
1 Main axle 1 Refer to removal section.
2 Drive axle 1 Refer to removal section.
3 Shift cam 1 Refer to removal section.
4 Shift fork 3 1 Refer to removal section.
5 Shift fork 2 1 Refer to removal section.
6 Shift fork 1 1 Refer to removal section.
7 Collar 1

5-64
 TRANSMISSION, SHIFT CAM AND SHIFT FORK

REMOVING THE TRANSMISSION CHECKING THE BEARING INSTALLING THE TRANSMISSION

1. Remove: 1. Inspect: 1. Install:
• Main axle "1" • Bearing "1" • 5th pinion gear (19T) "1"
• Drive axle "2" Rotate inner race with a finger. • 3rd pinion gear (17T) "2"
• Shift cam Rough spot/seizure → Replace. • Collar "3"
• Shift fork 3 • 4th pinion gear (21T) "4"
• Shift fork 2 • 2nd pinion gear (16T) "5"
• Shift fork 1 To main axle "6".

• Remove assembly with the collar Apply the molybdenum disulfide oil
"3" installed to the crankcase. on the inner and end surface of the
• Remove assembly carefully. Note idler gear and on the inner surface of
the position of each part. Pay partic- the sliding gear, then install.
ular attention to the location and di- CHECKING THE SHIFT FORK,
rection of shift forks. SHIFT CAM AND SEGMENT
• Remove the main axle, drive axle, 1. Inspect:
shift cam and shift fork all together • Shift fork "1"
by tapping lightly on the transmis- Wear/damage/scratches → Re-
sion drive axle with a soft hammer. place.

2. Inspect:
CHECKING THE GEARS • Shift cam "1"
1. Inspect: • Segment "2" 2. Install:
• Matching dog "a" Wear/damage → Replace. • 2nd wheel gear (28T) "1"
• Gear teeth "b"
• 4th wheel gear (23T) "2"
• Shift fork groove "c"
• 3rd wheel gear (23T) "3"
Wear/damage → Replace.
• 5th wheel gear (17T) "4"
• 1st wheel gear (31T) "5"
• O-ring "6"
To drive axle "7".

• Apply the molybdenum disulfide oil

3. Check:
on the inner and end surface of the
• Shift fork movement
idler gear and on the inner surface
Unsmooth operation → Replace
2. Inspect: of the sliding gear, then install.
shift fork.
• O-ring "1" • Apply the lithium soap base grease
Damage → Replace. on the O-ring.

For a malfunctioning shift fork, re-

3. Check: place not only the shift fork itself but
• Gears movement the two gears each adjacent to the
Unsmooth movement→Repair or shift fork.
replace.

5-65
 TRANSMISSION, SHIFT CAM AND SHIFT FORK

3. Install:
• Washer "1"
• Circlip "2"

• Be sure the circlip sharp-edged cor-

ner "a" is positioned opposite side
to the washer and gear "b".
• Install the circlip with its ends "c"
settled evenly on the spline crests.

6. Install:
• Transmission assembly "1"
To left crankcase "2".

Apply the engine oil on the bearings

and guide bars.

4. Install:
• Collar "1"

• Apply the lithium soap base grease

on the oil seal lip. 7. Check:
• When installing the collar into the • Shifter operation
crankcase, pay careful attention to • Transmission operation
the crankcase oil seal lip. Unsmooth operation → Repair.

5. Install:
• Shift fork 1 (L) "1"
• Shift fork 2 (C) "2"
• Shift fork 3 (R) "3"
• Shift cam "4"
To main axle and drive axle.

• Apply the engine oil on the shift fork

grooves.
• Mesh the shift fork #1 (L) with the
4th wheel gear "5" and #3 (R) with
the 5th wheel gear "7" on the drive
axle.
• Mesh the shift fork #2 (C) with the
3rd pinion gear "6" on the main ax-
le.

5-66
 FRONT WHEEL AND REAR WHEEL

CHASSIS
This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles
(e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are request-
ed not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to
servicing trouble and mechanical damage.

FRONT WHEEL AND REAR WHEEL

REMOVING THE FRONT WHEEL

21 Nm (2.1 m kg, 15 ft lb)

21 Nm (2.1 m kg, 15 ft lb)

90 Nm (9.0 m kg, 65 ft lb)

12 Nm (1.2 m kg, 8.7 ft lb)

Order Part name Q'ty Remarks

Hold the machine by placing the suitable stand
Refer to "HANDLING NOTE".
under the engine.
1 Bolt (axle holder) 4 Only loosening.
2 Nut (front wheel axle) 1
3 Front wheel axle 1
4 Front wheel 1
5 Speed sensor 1
6 Collar 1
7 Oil seal 1
8 Bearing 2 Refer to removal section.
9 Brake disc 1

6-1
 FRONT WHEEL AND REAR WHEEL

REMOVING THE REAR WHEEL

14 Nm (1.4 m kg, 10 ft lb)

125 Nm (12.5 m kg, 90 ft lb)

19 Nm (1.9 m kg, 13 ft lb)

50 Nm (5.0 m kg, 36 ft lb)

19 Nm (1.9 m kg, 13 ft lb)

Order Part name

Hold the machine by placing the suitable stand
under the engine.
Q'ty Remarks

Refer to "HANDLING NOTE".

6
1 Nut (rear wheel axle) 1
2 Rear wheel axle 1
3 Drive chain puller 2
4 Rear wheel 1 Refer to removal section.
5 Collar 2
6 Rear wheel sprocket 1
7 Oil seal 2
8 Circlip 1
9 Bearing 2 Refer to removal section.
10 Brake disc 1

6-2
 FRONT WHEEL AND REAR WHEEL

HANDLING NOTE

Support the machine securely so

there is no danger of it falling over.

REMOVING THE REAR WHEEL

1. Remove:
• Wheel "1"
CHECKING THE WHEEL AXLE
1. Measure:
Push the wheel forward and remove • Wheel axle bends
the drive chain "2". Out of specification → Replace.
Use the dial gauge "1".
Wheel axle bending limit:
0.5 mm (0.020 in)

INSTALLING THE FRONT WHEEL

The bending value is shown by one 1. Install:
half of the dial gauge reading. • Bearing (left) "1"
• Spacer "2"
REMOVING THE WHEEL BEARING • Bearing (right) "3"
1. Remove: • Oil seal "4"
Do not attempt to straighten a bent
• Bearing "1"
axle.
• Apply the lithium soap base grease
Remove the bearing using a general on the bearing and oil seal lip when
bearing puller "2". installing.
• Use a socket that matches the out-
side diameter of the race of the
bearing.
• Left side of bearing shall be in-
stalled first.
• Install the oil seal with its manufac-
CHECKING THE BRAKE DISC ture's marks or numbers facing out-
1. Measure: ward.
• Brake disc deflection (only rear
CHECKING THE WHEEL brake disc)
1. Measure: Use the dial gauge "1".
• Wheel runout Do not strike the inner race of the
Out of specification → Inspect
Out of limit → Repair/replace. bearing. Contact should be made
wheel runout.
only with the outer race.
Wheel runout limit: If wheel runout is in good condi-
Radial "1": 2.0 mm tion, replace the brake disc.
(0.08 in) Brake disc deflection lim-
Lateral "2": 2.0 mm it:
(0.08 in) Rear:
<Limit>: 0.15 mm
(0.006 in)
2. Measure:
• Brake disc thickness "a"
Out of limit → Replace.
Brake disc thickness:
Front:
2. Inspect: 3.0 mm (0.12 in)
• Bearing <Limit>: 2.5 mm (0.10
Rotate inner race with a finger. in)
Rough spot/seizure → Replace. Rear:
4.0 mm (0.16 in)
<Limit>: 3.5 mm (0.14
Replace the bearings, oil seal and in)
wheel collar as a set.

6-3
 FRONT WHEEL AND REAR WHEEL

2. Install:
• Brake disc "1"
• Bolt (brake disc) "2"
Bolt (brake disc):
12 Nm (1.2 m•kg, 8.7
ft•lb)

Tighten the bolts in stage, using a

crisscross pattern.

6. Install: INSTALLING THE REAR WHEEL

• Wheel axle "1" 1. Install:
• Bearing (right) "1"
3. Install: • Circlip "2"
Apply the lithium soap base grease
• Collar "1" • Spacer "3"
on the wheel axle.
• Bearing (left) "4"
Apply the lithium soap base grease • Oil seal "5"
on the oil seal lip.
• Apply the lithium soap base grease
on the bearing and oil seal lip when
installing.
• Install the bearing with seal facing
outward.
• Use a socket that matches the out-
7. Install: side diameter of the race of the
• Nut (wheel axle) "1" bearing.
4. Install: Nut (wheel axle): • Right side of bearing shall be in-
• Speed sensor "1" 90 Nm (9.0 m•kg, 65 stalled first.
ft•lb) • Install the oil seal with its manufac-
ture's marks or numbers facing out-
• Apply the lithium soap base grease
ward.
on the oil seal lip of the speed sen-
sor.
• Make sure the two projections "a" in
the wheel hub are meshed with the Do not strike the inner race of the
two slots "b" in the speed sensor. bearing. Contact should be made
only with the outer race.

8. Tighten:
• Bolt (axle holder) "1"
Bolt (axle holder):
21 Nm (2.1 m•kg, 15
ft•lb)

5. Install:
Before tightening the bolt, fit the
• Wheel
wheel axle to the axle holder by strok-
ing the front fork several times with
• Install the brake disc "1" between the front brake applied.
the brake pads "2" correctly.
• Make sure that the projections "a" in
the speed sensor fits over the stop-
per "b" on the front fork inner tube.

6-4
 FRONT WHEEL AND REAR WHEEL

2. Install: 5. Install: 9. Adjust:

• Brake disc "1" • Wheel • Drive chain slack "a"
• Bolt (brake disc) "2" Drive chain slack:
Bolt (brake disc): Install the brake disc "1" between the 48–58 mm (1.9–2.3 in)
14 Nm (1.4 m•kg, 10 brake pads "2" correctly.
ft•lb) Refer to "ADJUSTING THE
DRIVE CHAIN SLACK" section in
the CHAPTER 3.
Tighten the bolts in stage, using a
crisscross pattern.

6. Install:
• Drive chain "1"
10. Tighten:
Push the wheel "2" forward and install • Nut (wheel axle) "1"
the drive chain.
3. Install: Nut (wheel axle):
• Rear wheel sprocket "1" 125 Nm (12.5 m•kg, 90
• Bolt (rear wheel sprocket) "2" ft•lb)
• Washer (rear wheel sprocket) "3"
• Locknut "2"
• Nut (rear wheel sprocket) "4"
Locknut:
Nut (rear wheel sprock- 19 Nm (1.9 m•kg, 13
et): ft•lb)
50 Nm (5.0 m•kg, 36
ft•lb)
7. Install:
• Left drive chain puller "1"
Tighten the nuts in stage, using a • Wheel axle "2"
crisscross pattern.
• Install the left drive chain puller, and
insert the wheel axle from left side.
• Apply the lithium soap base grease
on the wheel axle.

4. Install:
• Collar "1"

Apply the lithium soap base grease

on the oil seal lip. 8. Install:
• Right drive chain puller "1"
• Washer "2"
• Nut (wheel axle) "3"

Temporarily tighten the nut (wheel

axle) at this point.

6-5
 FRONT BRAKE AND REAR BRAKE

FRONT BRAKE AND REAR BRAKE

REMOVING THE FRONT BRAKE

Order Part name Q'ty Remarks

Hold the machine by placing the suitable stand
Refer to "HANDLING NOTE".
under the engine.
Drain the brake fluid. Refer to removal section.
1 Brake hose holder (protector) 2
2 Brake hose holder (brake caliper) 1
3 Union bolt 2
4 Brake hose 1
5 Pad pin plug 1 Remove when loosening the pad pin.
Loosen when disassembling the brake cali-
6 Pad pin 1
per.
7 Brake caliper 1
8 Brake lever 1
9 Brake master cylinder bracket 1
10 Brake master cylinder 1

6-6
 FRONT BRAKE AND REAR BRAKE

REMOVING THE REAR BRAKE

Order Part name Q'ty Remarks

Hold the machine by placing the suitable stand
Refer to "HANDLING NOTE".
under the engine.
Refer to "FRONT WHEEL AND REAR
Rear wheel
WHEEL" section.
Drain the brake fluid. Refer to removal section.
1 Brake pedal 1
2 Brake master cylinder 1
3 Brake hose holder 2
4 Union bolt 2
5 Brake hose 1
6 Pad pin plug 1 Remove when loosening the pad pin.
Loosen when disassembling the brake cali-
7 Pad pin 1
per.
8 Brake caliper 1

6-7
 FRONT BRAKE AND REAR BRAKE

DISASSEMBLING THE BRAKE CALIPER

Order Part name Q'ty Remarks

A. Front
B. Rear
A B
1 Pad pin 1 1
2 Brake pad 2 2
3 Pad support 1 1
4 Brake caliper piston 2 1 Refer to removal section.
5 Brake caliper piston dust seal 2 1 Refer to removal section.
6 Brake caliper piston seal 2 1 Refer to removal section.

6-8
 FRONT BRAKE AND REAR BRAKE

DISASSEMBLING THE BRAKE MASTER CYLINDER

Order Part name Q'ty Remarks

A. Front
B. Rear
1 Brake master cylinder cap 1
2 Diaphragm 1
3 Reservoir float 1
4 Brake master cylinder boot 1
5 Circlip 1 Use a long nose circlip pliers.
6 Washer 1
7 Push rod 1
8 Brake master cylinder kit 1

6-9
 FRONT BRAKE AND REAR BRAKE

HANDLING NOTE REMOVING THE BRAKE CALIPER

PISTON
1. Remove:
Support the machine securely so • Brake caliper piston
there is no danger of it falling over. Use compressed air and proceed
carefully.
DRAINING THE BRAKE FLUID
1. Remove:
• Brake master cylinder cap "1" • Cover piston with rag and use ex-
• Protector (rear brake) treme caution when expelling
piston from cylinder.
Do not remove the diaphragm. • Never attempt to pry out piston.

Caliper piston removal steps:

a. Insert a piece of rag into the brake
caliper to lock one brake caliper. A. Front
b. Carefully force the piston out of B. Rear
the brake caliper cylinder with
CHECKING THE BRAKE MASTER
compressed air.
CYLINDER
1. Inspect:
• Brake master cylinder inner sur-
face "a"
Wear/scratches → Replace mas-
ter cylinder assembly.
Stains → Clean.

Use only new brake fluid.

A. Front
B. Rear
2. Connect the transparent hose "2"
to the bleed screw "1" and place a
suitable container under its end.

A. Front
B. Rear
A. Front
B. Rear
REMOVING THE BRAKE CALIPER 2. Inspect:
PISTON SEAL KIT • Diaphragm "1"
A. Front 1. Remove: Crack/damage → Replace.
B. Rear • Brake caliper piston dust seal "1"
3. Loosen the bleed screw and drain • Brake caliper piston seal "2"
the brake fluid while pulling the le-
ver in or pushing down on the Remove the brake caliper piston
pedal. seals and brake caliper piston dust
seals by pushing them with a finger.

• Do not reuse the drained brake

fluid.
Never attempt to pry out brake cal- A. Front
• Brake fluid may erode painted
iper piston seals and brake caliper B. Rear
surfaces or plastic parts. Always
clean up spilled fluid immediate- piston dust seals.
ly.

Replace the brake caliper piston

seals and brake caliper piston dust
seals whenever a caliper is disas-
sembled.

6-10
 FRONT BRAKE AND REAR BRAKE

3. Inspect: (front brake only) CHECKING THE BRAKE HOSE

• Reservoir float "1" 1. Inspect:
Damage → Replace. • Brake hose "1"
Crack/damage → Replace.

4. Inspect:
• Brake master cylinder piston "1" HANDLING NOTE
• Brake master cylinder cup "2"
Wear/damage/score marks → Re-
place brake master cylinder kit. • All internal parts should be
cleaned in new brake fluid only. A. Front
• Internal parts should be lubricat- B. Rear
ed with brake fluid when in- 3. Install:
stalled. • Brake caliper piston "1"
• Replace the brake caliper piston
seals and brake caliper piston
Apply the brake fluid on the piston
dust seals whenever a caliper is
wall.
disassembled.
A. Front
INSTALLING THE BRAKE
B. Rear
CALIPER PISTON • Install the piston with its shallow
CHECKING THE BRAKE CALIPER 1. Clean: depressed side "a" facing the
1. Inspect: • Brake caliper brake caliper.
• Brake caliper cylinder inner sur- • Brake caliper piston seal • Never force to insert.
face "a" • Brake caliper piston dust seal
Wear/score marks → Replace • Brake caliper piston
brake caliper assembly. Clean them with brake fluid.
2. Install:
• Brake caliper piston seal "1"

• Brake caliper piston dust seal "2"

Always use new brake caliper pis-

A. Front ton seals and brake caliper piston
B. Rear dust seals.
2. Inspect:
• Brake caliper piston "1"
Wear/score marks → Replace • Apply the brake fluid on the brake
brake caliper piston assembly. caliper piston seal.
• Apply the silicone grease on the A. Front
brake caliper piston dust seal. B. Rear
Replace the brake caliper piston • Fit the brake caliper piston seals
seals and brake caliper piston dust and brake caliper piston dust seals
seals "2" whenever a caliper is dis- onto the slot on brake caliper cor-
assembled. rectly.

6-11
 FRONT BRAKE AND REAR BRAKE

INSTALLING THE FRONT BRAKE

CALIPER Apply the brake fluid on the brake
1. Install: master cylinder cup.
• Pad support "1"
• Brake pad "2"
• Pad pin "3"
After installing, cylinder cup
should be installed as shown di-
• Install the brake pads with their pro- rection. Wrong installation cause
jections "a" into the brake caliper re- 2. Install:
improper brake performance.
cesses "b". • Brake disc cover "1"
• Temporarily tighten the pad pin at • Bolt (brake disc cover) "2"
this point. Bolt (brake disc cover):
10 Nm (1.0 m•kg, 7.2
ft•lb)

2. Install:
• Brake caliper "1"
• Bolt (brake caliper) "2" 3. Install:
Bolt (brake caliper): • Brake caliper "1"
23 Nm (2.3 m•kg, 17 • Rear wheel "2"
ft•lb) Refer to "FRONT WHEEL AND A. Front
REAR WHEEL" section. B. Rear
3. Tighten: 4. Tighten: 3. Install:
• Pad pin "3" • Pad pin "3" • Spring "1"
Pad pin: Pad pin: To brake master cylinder piston
18 Nm (1.8 m•kg, 13 18 Nm (1.8 m•kg, 13 "2".
ft•lb) ft•lb)
4. Install: Install the spring at the smaller dia.
5. Install:
• Pad pin plug "4" side.
• Pad pin plug "4"
Pad pin plug: Pad pin plug:
3 Nm (0.3 m•kg, 2.2 3 Nm (0.3 m•kg, 2.2
ft•lb) ft•lb)

A. Front
B. Rear
4. Install:
• Brake master cylinder kit "1"
INSTALLING THE REAR BRAKE INSTALLING THE BRAKE • Washer (front brake) "2"
CALIPER MASTER CYLINDER KIT • Push rod (rear brake) "2"
1. Install: 1. Clean: • Circlip "3"
• Pad support "1" • Brake master cylinder • Brake master cylinder boot "4"
• Brake pad "2" • Brake master cylinder kit To brake master cylinder.
• Pad pin "3" Clean them with brake fluid.
2. Install:
• Apply the brake fluid on the brake
• Install the brake pads with their pro- • Brake master cylinder cup (prima-
master cylinder kit.
jections "a" into the brake caliper re- ry) "1"
• Apply the silicone grease on the tip
cesses "b". • Brake master cylinder cup (sec-
of the push rod.
• Temporarily tighten the pad pin at ondary) "2"
• When installing the circlip, use a
this point. To brake master cylinder piston
long nose circlip pliers.
"3".

6-12
 FRONT BRAKE AND REAR BRAKE

• Nut (brake lever) "3" 2. Install:

Nut (brake lever): • Brake master cylinder "1"
6 Nm (0.6 m•kg, 4.3 • Bolt (brake master cylinder) "2"
ft•lb) Bolt (brake master cylin-
der):
10 Nm (1.0 m•kg, 7.2
Apply the silicone grease on the ft•lb)
brake lever sliding surface, bolt and
contacting surface of the brake mas-
ter cylinder piston.

A. Front 3. Install:
B. Rear • Spring "1"
INSTALLING THE FRONT BRAKE • Brake pedal "2"
INSTALLING THE REAR BRAKE • O-ring "3"
MASTER CYLINDER
MASTER CYLINDER • Bolt (brake pedal) "4"
1. Install:
1. Install:
• Brake master cylinder "1" Bolt (brake pedal):
• Copper washer "1"
• Brake master cylinder bracket "2" 26 Nm (2.6 m•kg, 19
• Brake hose "2"
• Bolt (brake master cylinder brack- ft•lb)
• Union bolt "3"
et) "3"
Union bolt: • Clip "5"
Bolt (brake master cylin-
30 Nm (3.0 m•kg, 22
der bracket):
ft•lb) Apply the lithium soap base grease
9 Nm (0.9 m•kg, 6.5
on the bolt, O-ring and brake pedal
ft•lb)
bracket.
Always use new copper washers.
• Install the bracket so that the arrow
mark "a" face upward.
• First tighten the bolts on the upper
side of the brake master cylinder
bracket, and then tighten the bolts
on the lower side.

4. Install:
• Pin "1"
• Washer "2"
Install the brake hose so that its • Cotter pin "3"
pipe portion "a" directs as shown
and lightly touches the projection After installing, check the brake pedal
"b" on the brake master cylinder. height. Refer to "ADJUSTING THE
2. Install: REAR BRAKE" section in the CHAP-
• Brake lever "1" TER 3.
• Bolt (brake lever) "2"
Bolt (brake lever):
6 Nm (0.6 m•kg, 4.3
ft•lb)

6-13
 FRONT BRAKE AND REAR BRAKE

INSTALLING THE FRONT BRAKE

HOSE
1. Install: Always use new copper washers.
• Copper washer "1"
• Brake hose "2"
• Union bolt "3"
Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb) 4. Pass the brake hose through the
front brake hose guides "1".

Always use new copper washers.

Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake caliper.

5. Install:
• Copper washer "1"
• Brake hose "2"
• Union bolt "3"
Union bolt:
Install the brake hose so that its
30 Nm (3.0 m•kg, 22
pipe portion "a" directs as shown
ft•lb)
and lightly touches the projection
"b" on the brake caliper. 2. Install:
• Brake hose holder "1"
Always use new copper washers. • Screw (brake hose holder) "2"
Screw (brake hose hold-
er):
3 Nm (0.3 m•kg, 2.2
ft•lb)

2. Install: After installing the brake hose

• Brake hose holder "1" holders, make sure the brake hose
• Bolt (brake hose holder) "2" does not contact the spring (rear
shock absorber). If it does, correct
Bolt (brake hose holder): Install the brake hose so that it its twist.
10 Nm (1.0 m•kg, 7.2 contacts the brake master cylinder
ft•lb) projection "a" and that its bent
portion "b" faces downward.

3. Install:
• Brake hose holder "1" INSTALLING THE REAR BRAKE
• Nut (brake hose holder) "2" HOSE
Nut (brake hose holder): 1. Install:
7 Nm (0.7 m•kg, 5.1 ft • Copper washer "1"
•lb) • Brake hose "2"
• Union bolt "3"
Union bolt:
Align the top "a" of the brake hose 30 Nm (3.0 m•kg, 22
holder with the paint "b" of the brake ft•lb)
hose.

6-14
 FRONT BRAKE AND REAR BRAKE

FILLING THE BRAKE FLUID 4. Install:

1. Fill: • Reservoir float (front brake)
• Brake fluid • Diaphragm
Until the fluid level reaches • Brake master cylinder cap "1"
"LOWER" level line "a". • Screw (bolt) {brake master cylin-
Recommended brake flu- der cap} "2"
id: Screw (bolt) {brake mas-
DOT #4 ter cylinder cap}:
2 Nm (0.2 m•kg, 1.4
ft•lb)
• Use only the designated quality
brake fluid:
otherwise, the rubber seals may After installation, while pulling the
deteriorate, causing leakage and brake lever in or pushing down on
poor brake performance. the brake pedal, check whether
• Refill with the same type of brake there is any brake fluid leaking
fluid; where the union bolts are installed
mixing fluids may result in a respectively at the brake master
harmful chemical reaction and cylinder and brake caliper.
lead to poor performance.
• Be careful that water does not
enter the master cylinder when
refilling. Water will significantly
lower the boiling point of the flu-
id and may result in vapor lock.

Brake fluid may erode painted sur-

faces or plastic parts. Always
clean up spilled fluid immediately.

A. Front
B. Rear
5. Install: (rear brake only)
• Protector "1"
• Bolt (protector) "2"
Bolt (protector):
7 Nm (0.7 m•kg, 5.1
ft•lb)

A. Front
B. Rear
2. Air bleed:
• Brake system
Refer to "BLEEDING THE HY-
DRAULIC BRAKE SYSTEM" sec-
tion in the CHAPTER 3.
3. Inspect:
• Brake fluid level
Fluid at lower level → Fill up.
Refer to "CHECKING THE
BRAKE FLUID LEVEL" section in
the CHAPTER 3.

6-15
 FRONT FORK

FRONT FORK
REMOVING THE FRONT FORK

Order Part name Q'ty Remarks

A. For CDN
Hold the machine by placing the suitable stand
Refer to "HANDLING NOTE".
under the engine.
Refer to "FRONT WHEEL AND REAR
Front wheel
WHEEL" section.
Refer to "FRONT BRAKE AND REAR
Front brake caliper
BRAKE" section.
Headlight
Handlebar Refer to "HANDLEBAR" section.
1 Protector 1
2 Pinch bolt (upper bracket) 2 Only loosening.
3 Cap bolt 1 Loosen when disassembling the front fork.
4 Pinch bolt (lower bracket) 2 Only loosening.
5 Front fork 1

6-16
 FRONT FORK

DISASSEMBLING THE FRONT FORK

Order Part name Q'ty Remarks

1 Front fork cap bolt 1 Refer to removal section.
2 Fork spring 1 Drain the fork oil.
3 Dust seal 1 Refer to removal section.
4 Stopper ring 1 Refer to removal section.
5 Inner tube 1 Refer to removal section.
6 Outer tube 1
7 Piston metal 1
8 Slide metal 1
9 Oil seal washer 1
10 Oil seal 1
11 Spring guide 1
12 Base valve 1 Refer to removal section.
13 Damper rod 1 Refer to removal section.

6-17
 FRONT FORK

HANDLING NOTE REMOVING THE INNER TUBE CHECKING THE DAMPER ROD
1. Remove: 1. Inspect:
• Dust seal "1" • Damper rod "1"
Support the machine securely so • Stopper ring "2" Bend/damage→Replace damper
there is no danger of it falling over. Using slotted-head screwdriver. rod.

The front fork requires careful atten- Take care not to scratch the inner The front fork with a built-in piston
tion. So it is recommended that the tube. rod has a very sophisticated inter-
front fork be maintained at the deal- nal construction and is particularly
ers. sensitive to foreign material.
Use enough care not to allow any
foreign material to come in when
To prevent an accidental explosion the oil is replaced or when the
of air, the following instructions front fork is disassembled and re-
should be observed: assembled.
• The front fork with a built-in pis-
ton rod has a very sophisticated
2. Remove:
internal construction and is par-
• Inner tube "1"
ticularly sensitive to foreign ma-
terial. Use enough care not to
allow any foreign material to Oil seal removal steps:
come in when the oil is replaced a. Push in slowly "a" the inner tube
or when the front fork is disas- just before it bottoms out and then
sembled and reassembled. pull it back quickly "b".
b. Repeat this step until the inner CHECKING THE BASE VALVE
• Before removing the cap bolts or
tube can be pulled out from the 1. Inspect:
front forks, be sure to extract the
outer tube. • Valve assembly "1"
air from the air chamber com-
Wear/damage → Replace.
pletely.
• O-ring "2"
REMOVING THE FRONT FORK Damage → Replace.
CAP BOLT
1. Remove:
• Front fork cap bolt "1"
From the outer tube.

Before removing the front fork from

the machine, loosen the front fork cap REMOVING THE DAMPER ROD
bolt. 1. Remove: CHECKING THE FORK SPRING
• Base valve "1" 1. Measure:
• Damper rod "2" • Fork spring free length "a"
Out of specification → Replace.
Use a damper rod holder "3" to lock Fork spring free length:
the damper rod. 460 mm (18.1 in)
<Limit>: 455 mm (17.9
Damper rod holder: in)
YM-01494/90890-01494
2. Remove:
• Front fork cap bolt "1"

Hold the locknut "2" and remove the

front fork cap bolt.

6-18
 FRONT FORK

CHECKING THE INNER TUBE ASSEMBLING THE FRONT FORK 5. Install:

1. Inspect: 1. Wash the all parts in a clean sol- • Spring guide "1"
• Inner tube surface "a" vent. • Locknut "2"
Score marks → Repair or replace. 2. Install: To damper rod "3".
Use #1,000 grit wet sandpaper. • Damper rod "1"
Damaged oil lock piece → Re- To inner tube "2". • Install the spring guide with its
place. smaller dia.end "a" facing down-
• Inner tube bends ward.
Out of specification → Replace. To install the damper rod into the
• With its thread "b" facing upward,
Use the dial gauge "1". inner tube, hold the inner tube
fully finger tighten the locknut onto
aslant. If the inner tube is held ver-
Inner tube bending limit: the damper rod.
tically, the damper rod may fall into
0.2 mm (0.008 in) it, damaging the valve inside.

The bending value is shown by one

half of the dial gauge reading.

Do not attempt to straighten a bent

inner tube as this may dangerous- 6. Install:
ly weaken the tube. • Dust seal "1"
3. Install:
• Stopper ring "2"
• Copper washer "1"
• Oil seal "3"
• O-ring "2"
• Oil seal washer "4"
• Base valve "3"
• Slide metal "5"
To inner tube "4".
To inner tube "6".

• Apply the fork oil on the inner tube.

• When installing the oil seal, use vi-
CHECKING THE OUTER TUBE nyl seat "a" with fork oil applied to
1. Inspect: protect the oil seal lip.
• Outer tube "1" • Install the oil seal with its manufac-
Score marks/wear/damage → Re- ture's marks or number facing the
place. 4. Tighten: axle holder side.
• Base valve "1" • Install the oil seal washer with its
projections "b" facing upward.
Base valve:
55 Nm (5.5 m•kg, 40
ft•lb)

• Use a damper rod holder "2" to lock

the damper rod "3".
CHECKING THE FRONT FORK • Apply the LOCTITE® on the base
CAP BOLT valve thread.
1. Inspect:
• Front fork cap bolt "1" Damper rod holder:
• O-ring "2" YM-01494/90890-01494
• Air bleed screw "3"
Wear/damage → Replace.

6-19
 FRONT FORK

7. Install: 10. Install: 14. Compress the front fork fully.

• Piston metal "1" • Oil seal "1" 15. Fill:
• Front fork oil
Install the piston metal onto the slot Press the oil seal into the outer tube Until outer tube top surface with
on inner tube. with fork seal driver "2". recommended fork oil "1".
Recommended oil:
Fork seal driver: Suspension oil "S1"
YM-A0948/90890-01502

• Be sure to use recommended

fork oil. If other oils are used,
they may have an excessively ad-
verse effect on the front fork per-
8. Install: formance.
• Outer tube "1" • Never allow foreign materials to
To inner tube "2". enter the front fork.
11. Install:
• Stopper ring "1"

Fit the stopper ring correctly in the

groove in the outer tube.

9. Install:
• Slide metal "1" 16. After filling, pump the damper rod
• Oil seal washer "2" "1" slowly up and down more than
To outer tube slot. 10 times to distribute the fork oil.

Press the slide metal into the outer

tube with fork seal driver "3". 12. Install:
• Dust seal "1"
Fork seal driver:
YM-A0948/90890-01502 Apply the lithium soap base grease
on the inner tube.
17. Fill:
• Front fork oil
Until outer tube top surface with
recom-mended fork oil once
more.
18. After filling, pump the outer tube
"1" slowly up and down (about
200 mm (7.9 in) stroke) to distrib-
13. Check: ute the fork oil once more.
• Inner tube smooth movement
Tightness/binding/rough spots → Be careful not to excessive full stroke.
Repeat the steps 2 to 12. A stroke of 200 mm (7.9 in) or more
will cause air to enter. In this case, re-
peat the steps 15 to 18.

6-20
 FRONT FORK

19. Wait ten minutes until the air bub- 21. Measure:
bles have been removed from the • Distance "a"
front fork, and the oil has dis- Out of specification → Turn into
pense evenly in system before the locknut.
setting recommended oil level. Distance "a":
18 mm (0.71 in) or more
Fill with the fork oil up to the top end Between damper rod
of the outer tube, or the fork oil will not "1" top and locknut "2"
spread over to every part of the front top. 25. Tighten:
forks, thus making it impossible to ob- • Front fork cap bolt (locknut) "1"
tain the correct level. Front fork cap bolt (lock-
Be sure to fill with the fork oil up to the nut):
top of the outer tube and bleed the 29 Nm (2.9 m•kg, 21
front forks. ft•lb)
20. Measure:
• Oil level (left and right) "a" Hold the locknut "2" and tighten the
Out of specification → Adjust. front fork cap bolt with specified
Standard oil level: 22. Loosen: torque.
132 mm (5.20 in) • Rebound damping adjuster "1"
Extent of adjustment:
95–150 mm (3.74–5.91 • Loosen the rebound damping ad-
in) juster finger tight.
From top of outer tube • Record the set position of the ad-
with inner tube and juster (the amount of turning out the
damper rod "1" fully fully turned in position).
compressed without
spring.
26. Install:
• Front fork cap bolt "1"
Be sure to install the spring guide "2" To outer tube.
when checking the oil level.
Temporarily tighten the cap bolt.

Never fail to make the oil level ad-

23. Install:
justment between the maximum
• Push rod "1"
and minimum level and always ad-
• Fork spring "2"
just each front fork to the same
setting. Uneven adjustment can
cause poor handling and loss of • Install the fork spring with the
stability. damper rod "3" pulled up.
• After installing the fork spring, hold
the damper rod end so that it will not 27. Install:
go down. • Protector guide "1"

Install the protector guide with its wid-

er side "a" facing downward.

24. Install:
• Spring seat "1"
• Front fork cap bolt "2"

Fully finger tighten the front fork cap

bolt onto the damper rod.

6-21
 FRONT FORK

INSTALLING THE FRONT FORK 7. Install:

1. Install: • Protector "1"
• Front fork "1" • Bolt (protector) "2"
Bolt (protector):
• Temporarily tighten the pinch bolts 7 Nm (0.7 m•kg, 5.1
(lower bracket). ft•lb)
• Do not tighten the pinch bolts (up-
per bracket) yet.
5. Install:
• Speed sensor lead "1"
• Plate 1 "2"
• Bolt (plate 1) "3"
Bolt (plate 1):
4 Nm (0.4 m•kg, 2.9 ft •
lb)
8. Adjust:
To right protector "4". • Rebound damping force
2. Tighten:
• Front fork cap bolt Install the speed sensor lead so that Turn in the damping adjuster "1" fin-
Front fork cap bolt: its paint "a" directs as shown and ger-tight and then turn out to the orig-
30 Nm (3.0 m•kg, 22 align the bottom "b" of the plate 1 with inally set position.
ft•lb) the same paint.

3. Adjust:
• Front fork top end "a"
Front fork top end (stan-
dard) "a":
5 mm (0.20 in)

6. Install:
• Speed sensor lead "1"
• Plate 2 "2"
• Screw (plate 2) "3"
Screw (plate 2):
0.5 Nm (0.05 m•kg, 0.36
4. Tighten:
ft•lb)
• Pinch bolt (upper bracket) "1"
Pinch bolt (upper brack- To right protector "4".
et):
21 Nm (2.1 m•kg, 15 Install the plate 2 in the direction as
ft•lb) shown.

• Pinch bolt (lower bracket) "2"

Pinch bolt (lower brack-
et):
21 Nm (2.1 m•kg, 15
ft•lb)

Tighten the lower bracket to speci-

fied torque. If torqued too much, it
may cause the front fork to mal-
function.

6-22
 HANDLEBAR

HANDLEBAR
REMOVING THE HANDLEBAR

Order Part name Q'ty Remarks

Headlight
1 Hot starter cable 1 Disconnect at the lever side.
2 Hot starter lever holder 1
3 Clutch cable 1 Disconnect at the lever side.
4 Clutch lever holder 1 Disconnect the clutch switch lead.
5 Engine stop switch 1 Disconnect the engine stop switch lead.
6 Brake master cylinder 1 Refer to removal section.
7 Start switch 1 Disconnect the start switch lead.
8 Throttle cable cap 1
9 Throttle cable #1 (pulled) 1 Disconnect at the throttle side.
10 Throttle cable #2 (pushed) 1 Disconnect at the throttle side.
11 Right grip 1 Refer to removal section.
12 Tube guide 1
13 Left grip 1 Refer to removal section.
14 Handlebar upper holder 2
15 Handlebar 1
16 Handlebar lower holder 2

6-23
 HANDLEBAR

REMOVING THE BRAKE MASTER INSTALLING THE HANDLEBAR

CYLINDER 1. Install:
1. Remove: • Handlebar lower holder "1"
• Brake master cylinder bracket "1" • Washer "2"
• Brake master cylinder "2" • Nut (handlebar lower holder) "3"

• Install the handlebar lower holder

• Do not let the brake master cylin-
with its side having the greater dis-
der hang on the brake hose.
tance "a" from the mounting bolt
• Keep the brake master cylinder
center facing forward.
cap side horizontal to prevent air
• Apply the lithium soap base grease
from coming in.
on the thread of the handlebar low-
er holder.
• Installing the handlebar lower hold-
er in the reverse direction allows the
front-to-rear offset amount of the
handlebar position to be changed.
• Do not tighten the nut yet.

REMOVING THE GRIP

1. Remove:
• Grip "1"

Blow in air between the handlebar or

tube guide and the grip. Then remove
the grip which has become loose.

3. Tighten:
• Nut (handlebar lower holder) "1"
Nut (handlebar lower
2. Install:
holder):
CHECKING THE HANDLEBAR • Handlebar "1"
34 Nm (3.4 m•kg, 24
1. Inspect: • Handlebar upper holder "2"
ft•lb)
• Handlebar "1" • Bolt (handlebar upper holder) "3"
Bends/cracks/damage → Re- Bolt (handlebar upper
place. holder):
28 Nm (2.8 m•kg, 20
ft•lb)
Do not attempt to straighten a bent
handlebar as this may dangerous-
ly weaken the handlebar. • The handlebar upper holder should
be installed with the punched mark
"a" forward. 4. Install:
• Install the handlebar so that the • Left grip "1"
marks "b" are in place on both Apply the adhesive to the handle-
sides. bar "2".
• Install the handlebar so that the pro-
jection "c" of the handlebar upper • Before applying the adhesive, wipe
holder is positioned at the mark on off grease or oil on the handlebar
the handlebar as shown. surface "a" with a lacquer thinner.
• First tighten the bolts on the front • Install the left grip to the handlebar
side of the handlebar upper holder, so that the line "b" between the two
and then tighten the bolts on the arrow marks faces straight upward.
rear side.

6-24
 HANDLEBAR

7. Install: 10. Install:

• Throttle cables "1" • Start switch "1"
To tube guide "2". • Brake master cylinder "2"
• Brake master cylinder bracket "3"
Apply the lithium soap base grease • Bolt (brake master cylinder brack-
on the throttle cable end and tube et) "4"
guide cable winding portion. Bolt (brake master cylin-
der bracket):
5. Install: 9 Nm (0.9 m•kg, 6.5
• Right grip "1" ft•lb)
• Collar "2"
Apply the adhesive on the tube • Clamp "5"
guide "3".
• The start switch and brake master
• Before applying the adhesive, wipe cylinder bracket should be installed
off grease or oil on the tube guide according to the dimensions
surface "a" with a lacquer thinner. 8. Install: shown.
• Install the grip to the tube guide so • Throttle cable cap "1" • Install the bracket so that the arrow
that the grip match mark "b" and • Screw (throttle cable cap) "2" mark "a" faces upward.
tube guide slot "c" form the angle as Screw (throttle cable • First tighten the bolt on the upper
shown. cap): side of the brake master cylinder
4 Nm (0.4 m•kg, 2.9 bracket, and then tighten the bolt on
ft•lb) the lower side.

After tightening the screws, check

that the throttle grip "3" moves
smoothly. If it does not, retighten
the bolts for adjustment.

6. Install:
• Grip cap cover "1"
• Throttle grip "2" 11. Install:
• Engine stop switch "1"
Apply the lithium soap base grease • Clutch lever holder "2"
on the throttle grip sliding surface. • Bolt (clutch lever holder) "3"
Bolt (clutch lever holder):
4 Nm (0.4 m•kg, 2.9
9. Install: ft•lb)
• Grip cap cover "1"
• Cover (throttle cable cap) "2" • Hot starter lever holder "4"
• Bolt (hot starter lever holder) "5"
Bolt (hot starter lever
holder):
4 Nm (0.4 m•kg, 2.9
ft•lb)
• Clamp "6"

6-25
 HANDLEBAR

• The engine stop switch, clutch lever

holder and clamp should be in-
stalled according to the dimensions
shown.
• Pass the engine stop switch lead in
the middle of the clutch lever hold-
er.

12. Install:
• Clutch cable "1"
• Hot starter cable "2"

Apply the lithium soap base grease

on the clutch cable end and hot start-
er cable end.

13. Adjust:
• Clutch lever free play
Refer to "ADJUSTING THE
CLUTCH LEVER FREE PLAY"
section in the CHAPTER 3.
• Hot starter lever free play
Refer to "ADJUSTING THE HOT
STARTER LEVER FREE PLAY"
section in the CHAPTER 3.

6-26
 STEERING

STEERING
REMOVING THE STEERING

Order Part name Q'ty Remarks

A. For CDN
TIGHTENING STEPS:
• Tighten ring nut. 38 Nm (3.8 m•kg, 27 ft•lb)
• Loosen it one turn.
• Retighten it. 7 Nm (0.7 m•kg, 5.1 ft•lb)
Hold the machine by placing the suitable stand
Refer to "HANDLING NOTE".
under the engine.
Headlight
Handlebar Refer to "HANDLEBAR" section.
Front brake hose guide
Front fender
1 Multi-function display 1
2 Multi-function display bracket 1
3 Main switch 1 Disconnect the main switch lead.
4 Steering stem nut 1
5 Front fork 2 Refer to "FRONT FORK" section.
6 Upper bracket 1
7 Steering ring nut 1 Refer to removal section.

6-27
 STEERING

Order Part name Q'ty Remarks

8 Lower bracket 1
9 Bearing race cover 1
10 Upper bearing 1
11 Lower bearing 1 Refer to removal section.
12 Bearing race 2 Refer to removal section.

6-28
 STEERING

HANDLING NOTE CHECKING THE STEERING STEM

1. Inspect:
• Steering stem "1"
Support the machine securely so Bend/damage → Replace.
there is no danger of it falling over.

REMOVING THE STEERING RING

NUT
1. Remove:
3. Install:
• Steering ring nut "1"
• Lower bracket "1"
Use the steering nut wrench "2".
Steering nut wrench: Apply the lithium soap base grease
YU-33975/90890-01403 CHECKING THE BEARING AND on the bearing, the portion "a" and
BEARING RACE thread of the steering stem.
1. Wash the bearings and bearing
Support the steering stem so that races with a solvent.
it may not fall down. 2. Inspect:
• Bearing "1"
• Bearing race
Pitting/damage → Replace bear-
ings and bearing races as a set.
Install the bearing in the bearing
races. Spin the bearings by hand.
If the bearings hang up or are not 4. Install:
smooth in their operation in the • Steering ring nut "1"
bearing races, replace bearings Steering ring nut:
REMOVING THE LOWER and bearing races as a set. 7 Nm (0.7 m•kg, 5.1 ft•
BEARING lb)
1. Remove:
• Lower bearing "1" Tighten the steering ring nut using
Use the floor chisel "2". the steering nut wrench "2".
Refer to "CHECKING AND AD-
JUSTING THE STEERING
Take care not to damage the steer- HEAD" section in the CHAPTER
ing shaft thread. 3.
INSTALLING THE LOWER
BRACKET
1. Install:
• Lower bearing "1"

Apply the lithium soap base grease

on the dust seal lip and bearing inner
circumference.
5. Check the steering stem by turn-
REMOVING THE BEARING RACE ing it lock to lock. If there is any
1. Remove: binding, remove the steering stem
• Bearing race "1" assembly and inspect the steer-
Remove the bearing race using ing bearings.
long rod "2" and the hammer.

2. Install:
• Bearing race
• Upper bearing "1"
• Bearing race cover "2"
6. Install:
Apply the lithium soap base grease • Washer "1"
on the bearing and bearing race cov- • Collar "2"
er lip.
Install the collar "2" with the larger in-
side diameter facing downward.

6-29
 STEERING

• Multi-function display "2"

Multi-function display:
4 Nm (0.4 m•kg, 2.9
ft•lb)

Pass the throttle cables "3", clutch ca-

ble "4" and hot starter cable "5" be-
7. Install: 10. After tightening the nut, check the tween the multi-function display
• Front fork "1" steering for smooth movement. If bracket and upper bracket.
• Upper bracket "2" not, adjust the steering by loosen-
• Main switch "3" ing the steering ring nut little by lit-
• Front brake hose guide bracket tle.
"4" 11. Adjust:
• Front reflector (For CDN) "5" • Front fork top end "a"
• Nut (front reflector) (For CDN) "6" Front fork top end (stan-
Nut (front reflector) (For dard) "a":
CDN) : 5 mm (0.20 in)
4 Nm (0.4 m•kg, 2.9 ft• 14. Install:
lb) • Holder "1"
• Front reflector bracket (For CDN) Holder:
"7" 13 Nm (1.3 m•kg, 9.4
ft•lb)
• Temporarily tighten the pinch bolts
• Clamp "2"
(lower bracket).
• Do not tighten the pinch bolts (up- Clamp:
per bracket) yet. 12. Tighten: 7 Nm (0.7 m•kg, 5.1
• Pinch bolt (upper bracket) "1" ft•lb)
Pinch bolt (upper brack-
et):
• Install so that the marking "a" on the
21 Nm (2.1 m•kg, 15
speed sensor lead aligns with the
ft•lb)
holder edge.
• Pinch bolt (lower bracket) "2" • Fasten the speed sensor lead to the
holder with the clamp.
Pinch bolt (lower brack-
et):
8. Install:
21 Nm (2.1 m•kg, 15
• Guide (speed sensor lead) "1"
ft•lb)

After installing the guide as shown,

pass the speed sensor lead through
Tighten the lower bracket to speci-
the guide.
fied torque. If torqued too much, it
may cause the front fork to mal-
function.

9. Install:
• Washer "1"
• Steering stem nut "2"
13. Install:
Steering stem nut: • Multi-function display bracket "1"
145 Nm (14.5 m•kg, 105
Multi-function display
ft•lb)
bracket:
7 Nm (0.7 m•kg, 5.1
ft•lb)

6-30
 SWINGARM

SWINGARM
REMOVING THE SWINGARM

Order Part name Q'ty Remarks

Hold the machine by placing the suitable stand
Refer to "HANDLING NOTE".
under the engine.
Refer to "FRONT BRAKE AND REAR
Brake hose holder
BRAKE" section.
Refer to "FRONT BRAKE AND REAR
Rear brake caliper
BRAKE" section.
Bolt (brake pedal) Shift the brake pedal backward.
Drive chain
1 Drive chain support 1
2 Lower chain tensioner 1
3 Bolt (rear shock absorber-relay arm) 1 Hold the swingarm.
4 Bolt (connecting rod) 1
5 Pivot shaft 1
6 Swingarm 1

6-31
 SWINGARM

DISASSEMBLING THE SWINGARM

Order Part name Q'ty Remarks

1 Cap 2 Refer to removal section.
2 Relay arm 1
3 Connecting rod 1
4 Collar 2
5 Oil seal 2
6 Thrust bearing 2
7 Bushing 2
8 Oil seal 8
9 Bearing 10 Refer to removal section.

6-32
 SWINGARM

HANDLING NOTE CHECKING THE RELAY ARM

1. Inspect:
• Bearing "1"
Support the machine securely so • Collar "2"
there is no danger of it falling over. Free play exists/unsmooth revolu-
tion/rust → Replace bearing and
REMOVING THE CAP
collar as a set.
1. Remove:
2. Inspect:
• Left cap "1"
• Oil seal "3"
Damage → Replace.
Remove with a slotted-head screw-
driver inserted under the mark "a" on
the left cap.

2. Install:
• Bearing "1"
CHECKING THE CONNECTING • Washer "2"
ROD • Oil seal "3"
1. Inspect: To relay arm.
REMOVING THE BEARING • Bearing "1"
1. Remove: • Collar "2" • Apply the molybdenum disulfide
• Bearing "1" Free play exists/unsmooth revolu- grease on the bearing when install-
tion/rust → Replace bearing and ing.
collar as a set. • Install the bearing by pressing it on
Remove the bearing by pressing its
2. Inspect: the side having the manufacture's
outer race.
• Oil seal "3" marks or numbers.
Damage → Replace. • Apply the molybdenum disulfide
grease on the washer.

Installed depth of bear-

ings "a":
Zero mm (Zero in)

CHECKING THE SWINGARM

1. Inspect: INSTALLING THE BEARING AND
• Bearing "1" OIL SEAL
• Bushing "2" 1. Install:
Free play exists/unsmooth revolu- • Bearing "1"
tion/rust → Replace bearing and • Oil seal "2"
bushing as a set. To swingarm.
2. Inspect:
• Oil seal "3" • Apply the molybdenum disulfide
Damage → Replace. grease on the bearing when install-
ing.
• Install the bearing by pressing it on
the side having the manufacture's
marks or numbers.
• First install the outer and then the
inner bearings to a specified depth 3. Install:
from inside. • Bearing "1"
• Oil seal "2"
Installed depth of bear- To connecting rod.
ings:
Outer "a": Zero mm
(Zero in)
Inner "b": 6.5 mm (0.26
in)

6-33
 SWINGARM

3. Install:
• Apply the molybdenum disulfide • Collar "1" • Apply the molybdenum disulfide
grease on the bearing when install- To connecting rod "2". grease on the pivot shaft.
ing. • Insert the pivot shaft from right side.
• Install the bearing by pressing it on Apply the molybdenum disulfide
the side having the manufacture's grease on the collar and oil seal lips.
marks or numbers.

Installed depth of bear-

ings "a":
Zero mm (Zero in)

7. Check:
• Swingarm side play "a"
4. Install: Free play exists → Replace thrust
• Connecting rod "1" bearing.
• Bolt (connecting rod) "2" • Swingarm up and down move-
• Washer "3" ment "b"
• Nut (connecting rod) "4" Unsmooth movement/binding/
INSTALLING THE SWINGARM rough spots → Grease or replace
Nut (connecting rod):
1. Install: bearings, bushings and collars.
80 Nm (8.0 m•kg, 58
• Bushing "1"
ft•lb)
• Thrust bearing "2"
• Oil seal "3" To relay arm "5".
• Collar "4"
To swingarm "5" Apply the molybdenum disulfide
grease on the bolt.
Apply the molybdenum disulfide
grease on the bushings, thrust bear-
ings, oil seal lips and contact surfaces 8. Install:
of the collar and thrust bearing. • Bolt (connecting rod) "1"
• Washer "2"
• Nut (connecting rod) "3"

• Apply the molybdenum disulfide

grease on the bolt.
5. Install:
• Do not tighten the nut yet.
• Relay arm"1"
• Bolt (relay arm) "2"
• Washer "3"
2. Install: • Nut (relay arm) "4"
• Collar "1" To swingarm.
• Washer "2"
To relay arm "3". • Apply the molybdenum disulfide
grease on the bolt circumference
Apply the molybdenum disulfide and threaded portion.
grease on the collars and oil seal lips. • Do not tighten the nut yet. 9. Install:
• Bolt (rear shock absorber-relay
arm) "1"
• Nut (rear shock absorber-relay
arm) "2"
Nut (rear shock absorb-
er-relay arm):
53 Nm (5.3 m•kg, 38
ft•lb)
6. Install:
• Swingarm "1" Apply the molybdenum disulfide
• Pivot shaft "2" grease on the bolt.
Pivot shaft:
85 Nm (8.5 m•kg, 61
ft•lb)

6-34
 SWINGARM

10. Tighten: 14. Install:

• Nut (connecting rod) "1" • Drive chain support "1"
Nut (connecting rod): • Drive chain support cover "2"
80 Nm (8.0 m•kg, 58 • Bolt {drive chain support [L = 50
ft•lb) mm (1.97 in)]} "3"
• Nut (drive chain support) "4"
Nut (drive chain sup-
port):
7 Nm (0.7 m•kg, 5.1
ft•lb)
• Bolt {drive chain support cover[L
= 10 mm (0.39 in)]} "5"
Bolt (drive chain support
11. Tighten: cover):
• Nut (relay arm) "1" 7 Nm (0.7 m•kg, 5.1
Nut (relay arm): ft•lb)
70 Nm (7.0 m•kg, 50
ft•lb)

12. Install:
• Cap "1"

Install the right cap with its mark "a"

facing forward.

13. Install:
• Bolt (lower chain tensioner) "1"
• Washer "2"
• Collar "3"
• Lower chain tensioner "4"
• Nut (lower chain tensioner) "5"
Nut (lower chain tension-
er):
16 Nm (1.6 m•kg, 11
ft•lb)

6-35
 REAR SHOCK ABSORBER

REAR SHOCK ABSORBER

REMOVING THE REAR SHOCK ABSORBER

Order Part name Q'ty Remarks

Hold the machine by placing the suitable stand
Refer to "HANDLING NOTE".
under the engine.
Refer to "REMOVING THE SEAT, FUEL
Seat and side cover TANK AND SIDE COVERS" section in the
CHAPTER 3.
Refer to "REMOVING THE EXHAUST PIPE
Silencer
AND SILENCER" section in the CHAPTER 3.
Refer to "CHANGING THE COOLANT" sec-
Drain the coolant.
tion in the CHAPTER 3.
Catch tank breather hose Disconnect at the catch tank side.
Catch tank hose Disconnect at the catch tank side.
Air induction hose (air cut-off valve-air filter case) Disconnect at the air filter case side.
Cylinder head breather hose Disconnect at the air filter case side.
Refer to "CHECKING AND CHARGING THE
Battery
BATTERY" section in the CHAPTER 3.
Disconnect the starter relay coupler.
Starter motor lead Disconnect at the starter relay side.
1 Locking tie 4

6-36
 REAR SHOCK ABSORBER

Order Part name Q'ty Remarks

2 Taillight coupler 1
3 CDI unit coupler 3
4 Plastic band 1
5 Clamp (air filter joint) 1 Only loosening.
6 Rear frame 1
7 Bolt (rear shock absorber-relay arm) 1 Hold the swingarm.
8 Bolt (rear shock absorber-frame) 1
9 Rear shock absorber 1
10 Locknut 1 Only loosening.
11 Adjuster 1 Only loosening.
12 Lower spring guide 1
13 Upper spring guide 1
14 Spring (rear shock absorber) 1
15 Bearing 2 Refer to removal section.

6-37
 REAR SHOCK ABSORBER

HANDLING NOTE CHECKING THE REAR SHOCK

ABSORBER
1. Inspect:
• Support the machine securely so • Damper rod "1"
there is no danger of it falling Bends/damage → Replace rear
over. shock absorber assembly.
• This rear shock absorber is pro- • Shock absorber "2"
vided with a separate type tank Oil leaks → Replace rear shock
filled with high-pressure nitro- REMOVING THE BEARING absorber assembly.
gen gas. To prevent the danger 1. Remove: Gas leaks → Replace rear shock
of explosion, read and under- • Stopper ring (upper bearing) "1" absorber assembly.
stand the following information • Spring "3"
before handling the shock ab- Damage → Replace spring.
Press in the bearing while pressing its
sorber. The manufacturer can Fatigue → Replace spring.
outer race and remove the stopper
not be held responsible for prop- Move spring up and down.
ring.
erty damage or personal injury • Spring guide "4"
that may result from improper Wear/damage → Replace spring
handling. guide.
• Never tamper or attempt to dis- • Bearing "5"
assemble the cylinder or the Free play exists/unsmooth revolu-
tank. tion/rust → Replace.
• Never throw the rear shock ab-
sorber into an open flame or
other high heat. The rear shock
absorber may explode as a re- 2. Remove:
sult of nitrogen gas expansion • Upper bearing "1"
and/ or damage to the hose.
• Be careful not to damage any Remove the bearing by pressing its
part of the gas tank. A damaged outer race.
gas tank will impair the damp-
ing performance or cause a
malfunction.
• Take care not to scratch the
contact surface of the piston
rod with the cylinder; or oil
could leak out.
• Never attempt to remove the
plug at the bottom of the nitro- INSTALLING THE BEARING
gen gas tank. It is very danger- 3. Remove: 1. Install:
ous to remove the plug. • Lower bearing "1" • Upper bearing "1"
• When scrapping the rear shock
absorber, follow the instruc- Remove the bearing by pressing its Install the bearing parallel until the
tions on disposal. outer race. stopper ring groove appears by
NOTES ON DISPOSAL (YAMAHA pressing its outer race.
DEALERS ONLY)
Before disposing the rear shock ab-
sorber, be sure to extract the nitrogen Do not apply the grease on the
gas from valve "1". Wear eye protec- bearing outer race because it will
tion to prevent eye damage from es- wear the rear shock absorber sur-
caping gas and/or metal chips. face on which the bearing is press
fitted.

To dispose of a damaged or worn-

out rear shock absorber, take the
unit to your Yamaha dealer for this
disposal procedure.

6-38
 REAR SHOCK ABSORBER

2. Install: 3. Adjust: • Nut (rear shock absorber-frame)

• Stopper ring (upper bearing) "1" • Spring length (installed) "3"
Refer to "ADJUSTING THE Nut (rear shock absorb-
REAR SHOCK ABSORBER er-frame):
After installing the stopper ring, push SPRING PRELOAD" section in 56 Nm (5.6 m•kg, 40
back the bearing until it contacts the the CHAPTER 3. ft•lb)
stopper ring. 4. Tighten:
• Locknut "1"
Apply the molybdenum disulfide
grease on the bolt.

3. Install: INSTALLING THE REAR SHOCK

• Lower bearing "1" ABSORBER
1. Install:
Install the bearing by pressing it on • Dust seal "1" 5. Install:
the side having the manufacture's • O-ring "2" • Bolt (rear shock absorber-relay
marks or numbers. • Collar "3" arm)"1"
• Nut (rear shock absorber-relay
arm) "2"
Installed depth of the • Apply the molybdenum disulfide
bearing "a": grease on the dust seal lips and col- Nut (rear shock absorb-
4 mm (0.16 in) lars. er-relay arm):
• Apply the lithium soap base grease 53 Nm (5.3 m•kg, 38
on the O-rings. ft•lb)

Apply the molybdenum disulfide

grease on the bolt.

INSTALLING THE SPRING (REAR

SHOCK ABSORBER)
1. Install: 2. Install:
• Spring "1" • Bushing "1"
• Upper spring guide "2" • Collar "2"
• Lower spring guide "3" • Dust seal "3"
6. Install:
• Rear frame "1"
• Apply the molybdenum disulfide
• Bolt [rear frame (upper)] "2"
grease on the bearing and dust seal
lips. Bolt [rear frame (upper)]:
• Install the dust seals with their lips 38 Nm (3.8 m•kg, 27
facing inward. ft•lb)
• Bolt [rear frame (lower)] "3"
2. Tighten: Bolt [rear frame (lower)]:
• Adjuster "1" 32 Nm (3.2 m•kg, 23
ft•lb)

3. Install:
• Rear shock absorber
4. Install:
• Bolt (rear shock absorber-frame)
"1"
• Washer "2"

6-39
 REAR SHOCK ABSORBER

7. Tighten:
• Screw (air filter joint) "1"
Screw (air filter joint):
3 Nm (0.3 m•kg, 2.2
ft•lb)

8. Install:
• Plastic band
• Taillight coupler
• Locking tie

6-40
 ELECTRICAL COMPONENTS AND WIRING DIAGRAM

ELECTRICAL
This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles
(e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are request-
ed not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to
servicing trouble and mechanical damage.

ELECTRICAL COMPONENTS AND WIRING DIAGRAM

ELECTRICAL COMPONENTS

1. Headlight 12. Taillight

2. Multi-function display 13. Neutral switch
3. Engine stop switch 14. Starter motor
4. Clutch switch 15. AC magneto
5. Diode 16. Rectifier/regulator
6. Starter relay diode 17. Ignition coil
7. Throttle position sensor 18. Spark plug
8. Starter relay 19. Start switch
9. Fuse 20. Main switch
10. Starting circuit cut-off relay 21. Speed sensor
11. CDI unit 22. Battery

7-1
 ELECTRICAL COMPONENTS AND WIRING DIAGRAM

WIRING DIAGRAM

1. Headlight COLOR CODE

2. Multi-function display B Black
3. Engine stop switch Br Brown
4. Clutch switch Ch Chocolate
5. Diode Dg Dark green
6. Starter relay diode G Green
7. Throttle position sensor Gy Gray
8. Starter relay L Blue
9. Fuse O Orange
10. Starting circuit cut-off relay R Red
11. CDI unit Sb Sky blue
12. Taillight W White
13. Neutral switch Y Yellow
14. Starter motor B/L Black/Blue

7
15. AC magneto B/W Black/White
16. Rectifier/regulator L/B Blue/Black
17. Ignition coil L/R Blue/Red
18. Spark plug L/Y Blue/Yellow
19. Start switch L/W Blue/White
20. Main switch R/B Red/Black
21. Speed sensor R/W Red/White
22. Battery

*1: For USA, CDN and EUROPE

*2: For AUS, NZ and ZA

7-2
 IGNITION SYSTEM

IGNITION SYSTEM
INSPECTION STEPS
Use the following steps for checking the possibility of the malfunctioning engine being attributable to ignition system failure
and for checking the spark plug which will not spark.
*1 Check fuse. No good → Replace fuse and check wire harness.
OK ↓
*2 Check battery. No good → Recharge or replace.
OK ↓
Spark gap test Spark → *3 Clean or replace spark plug.
No spark ↓
Check entire ignition system for connection. No good →
Repair or replace.
(couplers, leads and ignition coil)
OK ↓
Check engine stop switch. No good → Replace.
OK ↓
Check main switch. No good → Replace.
OK ↓
Check ignition coil. (primary coil and secondary No good →
Replace.
coil)
OK ↓
Check AC magneto. (pickup coil) No good → Replace.
OK ↓
Check neutral switch. No good → Repair or replace.
OK ↓
Replace CDI unit.
*1 marked: Refer to "CHECKING THE FUSE" section in the CHAPTER 3.
*2 marked: Refer to "CHECKING AND CHARGING THE BATTERY" section in the CHAPTER 3.
*3 marked: Only when the ignition checker is used.

• Remove the following parts before inspection.

1. Seat
2. Fuel tank
• Use the following special tools in this inspection.

Dynamic spark tester:

YM-34487
Ignition checker:
90890-06754
Pocket tester:
YU-3112-C/90890-03112

7-3
 IGNITION SYSTEM

SPARK GAP TEST CHECKING THE ENGINE STOP

1. Disconnect the ignition coil from SWITCH
spark plug. 1. Inspect:
2. Remove the ignition coil cap. • Engine stop switch conduction
3. Connect the dynamic spark tester Tester (+) lead → Black lead "1"
"1" (ignition checker "2") as Tester (-) lead → Black lead "2"
shown.
• Ignition coil "3" Result
• Spark plug "4" Conductive (while the 2. Inspect:
engine stop switch is • Main switch indicator light
pushed) Use 12 V battery.
Not conductive while it is pushed → Battery (+) lead → Red/Black lead
Replace. "1"
Conductive while it is freed → Re- Battery (-) lead → Black lead "2"
place. Indicator light does not come on →
Replace.
Set the tester selection position to "Ω
× 1".

A. For USA and CDN 3. Inspect:

B. Except for USA and CDN • Rubber part "a"
4. Kick the kickstarter crank. Tears/damage → Replace.
2. Inspect:
5. Check the ignition spark gap. • Rubber part "a"
6. Start engine, and increase spark Tears/damage → Replace.
gap until misfire occurs. (for USA
and CDN only)
Minimum spark gap:
6.0 mm (0.24 in)

CHECKING THE COUPLERS,

LEADS AND IGNITION COIL CHECKING THE IGNITION COIL
CONNECTION 1. Remove the ignition coil cap.
1. Check: 2. Inspect:
CHECKING THE MAIN SWITCH
• Couplers and leads connection • Primary coil resistance
1. Inspect:
Rust/dust/looseness/short-circuit Out of specification → Replace.
• Main switch conduction
→ Repair or replace. Tester (+) lead → Orange lead "1"
Tester (+) lead → Red lead "1"
• Ignition coil and spark plug as Tester (-) lead → Black lead "2"
Tester (-) lead → Brown lead "2"
they are fitted
Push in the ignition coil until it Primary Tester se-
Result
closely contacts the spark plug coil resis- lector posi-
Conductive (while the
hole in the cylinder head cover. tance tion
main switch is moved
to "ON") 0.08–0.10
Ω at 20 °C Ω×1
Not conductive while the main switch (68 °F)
is moved to "ON" → Replace.
Conductive while the main switch is
moved to "OFF" → Replace.

Set the tester selection position to

"Ω×1".

7-4
 ELECTRIC STARTING SYSTEM

3. Inspect: CHECKING THE NEUTRAL

• Secondary coil resistance SWITCH
Out of specification → Replace. 1. Inspect:
Tester (+) lead → Orange lead "1" • Neutral switch conduction
Tester (-) lead → Spark plug termi- Tester (+) lead→Sky blue lead "1"
nal "2" Tester (-) lead → Ground "2"

Secondary Tester se- Result

coil resis- lector posi- Conductive (while gear
tance tion is in neutral)
4.6–6.8 Not conductive while it is in neutral →
kΩat 20 °C kΩ × 1 Replace.
(68 °F) Conductive while it is engaged → Re-
place.

Set the tester selection position to "Ω

× 1".

4. Inspect:
• Sealed portion of ignition coil "a"
• Spark plug terminal pin "b"
• Threaded portion of spark plug "c"
Wear → Replace.
CHECKING THE CDI UNIT
Check all electrical components. If no
fault is found, replace the CDI unit.
Then check the electrical compo-
nents again.
ELECTRIC STARTING
SYSTEM 1. Battery
STARTING CIRCUIT CUT-OFF 2. Main fuse
CHECKING THE AC MAGNETO SYSTEM OPERATION 3. Main switch
1. Inspect: If the main switch is set to "ON", the 4. Starting circuit cut-off relay
• Pickup coil resistance starter motor can only operate if at 5. Start switch
Out of specification → Replace. least one of the following conditions is 6. Diode
Tester (+) lead → Red lead "1" met: 7. Clutch switch
Tester (-) lead → White lead "2" • The transmission is in neutral (the 8. Neutral switch
neutral switch is closed). 9. Starter relay
Tester se- • The clutch lever is pulled to the han- 10. Starter motor
Pickup coil
lector posi- dlebar (the clutch switch is closed).
resistance
tion The starting circuit cut-off relay pre-
248–372 Ω vents the starter motor from operating
at 20 °C (68 Ω × 100 when neither of these conditions has
°F) been met. In this instance, the start-
ing circuit cut-off relay is open so cur-
rent cannot reach the starter motor.
When at least one of the above con-
ditions has been met the starting cir-
cuit cut-off relay is closed and the
engine can be started by pressing the
start switch.

WHEN THE TRANSMISSION IS IN

NEUTRAL

WHEN THE CLUTCH LEVER IS

PULLED TO THE HANDLEBAR

7-5
 ELECTRIC STARTING SYSTEM

INSPECTION STEPS
If the starter motor will not operate, use the following inspection steps.
*1 Check fuse. No good → Replace fuse and check wire harness.
OK ↓
*2 Check battery. No good → Recharge or replace.
OK ↓
Check each coupler and wire connection. No good → Repair or replace.
OK ↓
*3 Check main switch. No good → Replace.
OK ↓
Check starter motor operation. No good → Repair or replace.
OK ↓
Check starting circuit cut-off relay. No good → Replace.
OK ↓
Check starter relay. No good → Replace.
OK ↓
*4 Check neutral switch. No good → Replace.
OK ↓
Check clutch switch. No good → Replace.
OK ↓
Check diode. No good → Replace.
OK ↓
Check start switch. No good → Replace.
*1 marked: Refer to "CHECKING THE FUSE" section in the CHAPTER 3.
*2 marked: Refer to "CHECKING AND CHARGING THE BATTERY" section in the CHAPTER 3.
*3 marked: Refer to "CHECKING THE MAIN SWITCH" section.
*4 marked: Refer to "CHECKING THE NEUTRAL SWITCH" section.

• Remove the following parts before inspection.

1. Seat
2. Rear fender
• Use 12 V battery in this inspection.
• Use the following special tools in this inspection.

Pocket tester:
YU-3112-C/90890-03112

7-6
 ELECTRIC STARTING SYSTEM

CHECKING THE COUPLERS AND CHECKING THE CLUTCH SWITCH

LEADS CONNECTION 1. Inspect:
1. Check: • Clutch switch conduction
• Couplers and leads connection Tester (+) lead → Black lead "1"
Rust/dust/looseness/short-circuit Tester (-) lead → Black lead "2"
→ Repair or replace.
CHECKING THE STARTER Result
MOTOR OPERATION Conductive (while the
1. Connect the positive battery ter- CHECKING THE STARTER RELAY clutch lever is pulled)
minal "1" and starter motor lead 1. Remove:
Not conductive while it is pulled → Re-
"2" with a jumper lead "3". • Starter relay
place.
Not operate → Repair or replace 2. Inspect:
Conductive while it is freed → Re-
the starter motor. • Starter relay conduction
place.
Use 12 V battery.
Battery (+) lead→Starter relay ter- Set the tester selection position to "Ω
• A wire that is used as a jumper
minal "1" × 1".
lead must have at least the same
Battery (-) lead → Starter relay ter-
capacity or more as that of the
minal "2"
battery lead, otherwise the jump-
er lead may burn. Tester (+) lead → Starter relay ter-
• This check is likely to produce minal "3"
sparks, therefore make sure Tester (-) lead → Starter relay ter-
nothing flammable is in the vicin- minal "4"
ity.
Result
Conductive (while the
battery is connected) CHECKING THE DIODE
1. Remove the diode from wire har-
Not conductive while the battery is
ness.
connected → Replace.
2. Inspect:
Conductive while the battery is not
• Diode continuity
connected → Replace.
Use pocket tester (tester selec-
tion position Ω × 1)
CHECKING THE STARTING Set the tester selection position to "Ω
× 1". Tester (+) → Blue/Red
CIRCUIT CUT-OFF RELAY terminal "1" Continu-
1. Remove: Tester (-) → Sky blue ous
• Starting circuit cut-off relay terminal "2"
2. Inspect:
• Starting circuit cut-off relay con- Tester (+) → Blue/Red
duction terminal "1" Continu-
Use 12 V battery. Tester (-) → Blue/Yel- ous
low terminal "3"
Battery (+) lead→Blue/Black lead
"1" Tester (+) → Sky blue
Battery (-) lead → Brown lead "2" terminal "2" No con-
Tester (-) → Blue/Red tinuous
Tester (+) lead → Blue/White lead terminal "1"
"3"
Tester (-) lead → Black lead "4" Tester (+) → Blue/Yel-
low terminal "3" No con-
Result Tester (-) → Blue/Red tinuous
Conductive (while the terminal "1"
battery is connected)
Incorrect continuity → Replace.
Not conductive while the battery is
connected → Replace.
Conductive while the battery is not
connected → Replace.

Set the tester selection position to "Ω

× 1".

7-7
 ELECTRIC STARTING SYSTEM

CHECKING THE START SWITCH

1. Inspect:
• Start switch conduction
Tester (+) lead → Black lead "1"
Tester (-) lead → Black lead "2"

Result
Conductive (while the
start switch is pushed)
Not conductive while it is pushed →
Replace.
Conductive while it is freed → Re-
place.

Set the tester selection position to "Ω

× 1".

2. Inspect:
• Rubber part "a"
Tears/damage → Replace.

7-8
 ELECTRIC STARTING SYSTEM

REMOVING THE STARTER MOTOR

Order Part name Q'ty Remarks

Refer to "REMOVING THE EXHAUST PIPE
Exhaust pipe
AND SILENCER" section in the CHAPTER 3.
1 Starter motor 1

7-9
 ELECTRIC STARTING SYSTEM

DISASSEMBLING THE STARTER MOTOR

Order Part name Q'ty Remarks

1 Starter motor front cover 1
2 Washer (starter motor front cover) 1
3 Gasket 2
4 Starter motor yoke 1
5 Armature assembly 1
6 Starter motor rear cover 1
7 Brush 2
8 Brush spring 2

7-10
 ELECTRIC STARTING SYSTEM

CHECKING AND REPAIRING THE Armature assembly: ASSEMBLING THE STARTER

STARTER MOTOR Commutator resis- MOTOR
1. Check: tance "1": 1. Install:
• Commutator 0.0189–0.0231 Ω at 20 • Brush spring "1"
Dirt → Clean with 600 grit sandpa- °C (68 °F) • Brush "2"
per. Insulation resistance
2. Measure: "2":
• Commutator diameter "a" Above 1 MΩat 20 °C
Out of specification→Replace the (68 °F)
starter motor.
Min. commutator diame-
ter:
16.6 mm (0.65 in)
2. Install:
• Armature assembly "1"
Install while holding down the
brush using a thin screw driver.
b. If any resistance is out of specifi-
cation, replace the starter motor. Be careful not to damage the brush
during installation.
5. Measure:
3. Measure: • Brush length "a"
• Mica undercut "a" Out of specification→Replace the
Out of specification → Scrape the brushes as a set.
mica to the proper measurement
Min. brush length:
with a hacksaw blade which has
3.5 mm (0.14 in)
been grounded to fit the commu-
tator.
Mica undercut: 3. Install:
1.5 mm (0.06 in) • Gasket "1"
• Starter motor yoke "2"

The mica must be undercut to ensure • Install the starter motor yoke with its
proper operation of the commutator. groove "a" facing front cover.
• Align the match mark "b" on the
6. Measure: starter motor yoke with the match
• Brush spring force mark "c" on the starter motor rear
Out of specification→Replace the cover.
brush springs as a set.
Brush spring force:
3.92–5.88 N (400–600
gf, 14.1–21.2 oz)
4. Measure:
• Armature assembly resistances
(commutator and insulation)
Out of specification→Replace the
starter motor. 4. Install:
• Gasket "1"
a. Measure the armature assembly • Circlip
resistances with the pocket tester. • Plain washer "2"
• Washer (starter motor front cover)
Pocket tester:
"3"
YU-3112-C/90890-
• Starter motor front cover "4"
03112

7-11
 ELECTRIC STARTING SYSTEM

• For installation, align the projec-

tions on the washer with the slots in
the front cover.
• Align the match mark "a" on the
starter motor yoke with the match
mark "b" on the starter motor front
cover.

5. Install:
• Gasket
• Bolt "1"
• O-ring "2"

Apply the lithium soap base grease

on the O-ring.

7-12
 CHARGING SYSTEM

CHARGING SYSTEM
INSPECTION STEPS
If the battery is not charged, use the following inspection steps.
*1 Check fuse. No good → Replace fuse and check wire harness.
OK ↓
*2 Check battery. No good → Recharge or replace.
OK ↓
Check each coupler and wire connection. No good → Repair or replace.
OK ↓
Check charging voltage. OK → Charging system is good.
No good ↓
Check AC magneto. (Charging coil) No good → Replace.
OK ↓
Replace rectifier/regulator.
*1 marked: Refer to "CHECKING THE FUSE" section in the CHAPTER 3.
*2 marked: Refer to "CHECKING AND CHARGING THE BATTERY" section in the CHAPTER 3.

• Remove the following parts before inspection.

1. Seat
2. Fuel tank
• Use the following special tools in this inspection.

Pocket tester:
YU-3112-C/90890-03112

7-13
 CHARGING SYSTEM

CHECKING THE COUPLERS AND

LEADS CONNECTION
1. Check:
• Couplers and leads connection
Rust/dust/looseness/short-circuit
→ Repair or replace.
CHECKING THE CHARGING
VOLTAGE
1. Start the engine.
2. Inspect:
• Charging voltage
Out of specification → If no failure
is found in checking the source
coil resistance, replace the rectifi-
er/regulator.
Tester (+) lead → Red lead "1"
Tester (-) lead → Black lead "2"

Tester se-
Charging
lector posi-
voltage
tion
14.0–15.0 V
at 5,000 r/ DCV-20
min

3. Inspect:
• Charging coil resistance
Out of specification → Replace.
Tester (+) lead → White lead "1"
Tester (-) lead → Ground "2"

Charging Tester se-

coil resis- lector posi-
tance tion
0.288–0.432
Ω at 20 °C Ω×1
(68 °F)

7-14
 THROTTLE POSITION SENSOR SYSTEM

THROTTLE POSITION SENSOR SYSTEM

INSPECTION STEPS
If the throttle position sensor will not operate, use the following inspection steps.
Check entire ignition system for connection. No good → Repair or replace.
OK ↓
Check throttle position sensor.(Throttle position No good →
Replace.
sensor coil)
OK ↓
Check CDI unit.(Throttle position sensor input No good →
Replace.
voltage)

Use the following special tools in this inspection.

Pocket tester:
YU-3112-C/90890-03112

7-15
 THROTTLE POSITION SENSOR SYSTEM

HANDLING NOTE 3. Inspect: 4. Install:

• Throttle position sensor coil vari- • Throttle position sensor "1"
able resistance • Screw (throttle position sensor)
Do not loosen the screw (throttle Check that the resistance in in- "2"
position sensor) "1" except when creased as the throttle grip is
changing the throttle position sen- moved from the full close position • Align the slot "a" in the throttle posi-
sor due to failure because it will to the full open position. tion sensor with the projection "b"
cause a drop in engine perfor- Out of specification → Replace. on the carburetor.
mance.
Tester (+) lead → Yellow lead "1" • Temporarily tighten the screw
Tester (-) lead → Black lead "2" (throttle position sensor).

Throttle posi- Tester

tion sensor coil selec-
variable resis- tor po-
tance sition
Full
Full
opene
closed
CHECKING THE COUPLERS AND d
LEADS CONNECTION kΩ×1
Zero –3 4–6 5. Install:
1. Check:
kΩat kΩat •Carburetor
• Couplers and leads connection
20°C 20 °C •Throttle position sensor coupler
Rust/dust/looseness/short-circuit
(68 °F) (68 °F) 6. Adjust:
→ Repair or replace.
•Engine idling speed
CHECKING THE THROTTLE Refer to "ADJUSTING THE EN-
POSITION SENSOR COIL GINE IDLING SPEED" section in
1. Inspect: the CHAPTER 3.
• Throttle position sensor coil resis- 7. Insert the thin electric conductors
tance "2" (lead) into the throttle position
Out of specification → Replace. sensor coupler "1", as shown, and
Tester (+) lead → Blue lead "1" connect the tester to them.
Tester (-) lead → Black lead "2" Tester (+) lead → Yellow lead "3"
CHANGING AND ADJUSTING THE
Throttle po- THROTTLE POSITION SENSOR Tester (-) lead → Black lead "4"
Tester se- 1. Remove:
sition sen-
lector posi- • Throttle position sensor coupler
sor coil
tion • Carburetor
resistance • Do not insert the electric conduc-
2. Remove: tors more than required because
4–6 kΩ at
kΩ×1 • Screw (throttle position sensor) it may reduce the waterproof
20°C (68 °F)
"1" function of the coupler.
• Throttle position sensor "2" • Make sure that a short-circuit
does not develop between the
Loosen the screw (throttle position terminals because it may cause
sensor) using the T25 bit. damage to electrical compo-
nents.

2. Loosen:
• Throttle stop screw "1"

Turn out the throttle stop screw until

the throttle shaft is in the full close po-
3. Replace:
sition.
• Throttle position sensor 8. Start the engine.

7-16
 THROTTLE POSITION SENSOR SYSTEM

9. Adjust: CHECKING THE THROTTLE

• Throttle position sensor output POSITION SENSOR INPUT
voltage VOLTAGE
1. Disconnect the throttle position
sensor coupler.
Adjustment steps:
2. Start the engine.
a. Adjust the installation angle of the
3. Inspect:
throttle position sensor "1" to ob-
• Throttle position sensor input volt-
tain the specified output voltage.
age
Out of specification→Replace the
Measure the output voltage accurate- CDI unit.
ly with a digital electronic voltmeter
that gives an easy reading of a small Tester (+) lead → Blue lead "1"
voltage. Tester (-) lead → Black/Blue lead
"2"
Throttle po- Throttle po-
Tester se- Tester se-
sition sen- sition sen-
lector posi- lector posi-
sor output sor input
tion tion
voltage voltage
0.58–0.78 V DCV 4–6 V DCV-20

10. Put the aligning marks "a" on the

throttle position sensor and car-
buretor.

11. Stop the engine.

12. Remove the carburetor.
13. Tighten:
• Screw (throttle position sensor)
"1"

Tighten the screw (throttle position

sensor) using the T25 bit.

14. Install the carburetor.

7-17
 LIGHTING SYSTEM

LIGHTING SYSTEM
INSPECTION STEPS
Refer to the following flow chart when inspecting the lighting system for possible problems.
Check the bulb and bulb socket. No good → Replace the bulb and/or bulb socket.
OK ↓
Check the taillight (LEDs). No good → Replace the taillight assembly.
OK ↓
Check the AC magneto. (Lighting coil) No good → Replace.
OK ↓
Check the entire lighting system proper for con- Improperly
Repair or replace.
nections. connected →
OK ↓
Check the rectifier/regulator. (Out-put voltage) No good → Replace.

• Remove the following parts before inspection.

1. Seat
2. Fuel tank
3. Left side cover
• Use the following special tools in this inspection.

Pocket tester:
YU-3112-C/90890-03112

7-18
 LIGHTING SYSTEM

CHECKING THE TAILLIGHT CHECKING THE RECTIFIER/

(LEDs) REGULATOR
1. Disconnect the taillight coupler. 1. Connect the battery leads.
2. Connect two jumper leads "1" 2. Start the engine.
from the battery terminals to the 3. Turn on the headlight and taillight
respective coupler terminal as by turning on the light switch.
shown. 4. Inspect:
Battery (+) terminal → Blue lead • Out-put voltage
"2" Out of specification → Replace
Battery (-) terminal → Black lead rectifier/regulator.
"3" Tester (+) lead → Yellow lead "1"
Tester (-) lead → Black lead "2"
3. Check:
• LED (for proper operation) Tester se-
Out-put
Does not light → Replace the tail- lector posi-
voltage
light assembly. tion
12.5–13.5 V
• A wire that is used as a jumper at 5,000 r/ ACV-20
lead must have at least the same min
capacity of the battery lead, oth-
erwise the jumper lead may burn.
• This check is likely to produce
sparks, therefore, make sure no
flammable gas or fluid is in the
vicinity.

CHECKING THE AC MAGNETO

1. Inspect:
• Lighting coil resistance
Out of specification → Replace.
Tester (+) lead → Yellow lead "1"
Tester (-) lead → Ground "2"

Lighting Tester se-

coil resis- lector posi-
tance tion
0.224–0.336
Ω at 20 °C Ω×1
(68 °F)

7-19
 SIGNALING SYSTEM

SIGNALING SYSTEM
INSPECTION STEPS
If the speedometer will not operate, use the following inspection steps.
*1 Check battery. No good → Recharge or replace.
OK ↓
Check each coupler and wire connection. No good → Repair or replace.
OK ↓
Check multi-function display. (Input voltage) No good → Replace wire harness.
OK ↓
Check multi-function display. (Output voltage) No good → Replace multi-function display.
OK ↓
Check speed sensor. No good → Replace.
*1 marked: Refer to "CHECKING AND CHARGING THE BATTERY" section in the CHAPTER 3.

• Remove the following parts before inspection.

1. Headlight
• Use the following special tools in this inspection.

Pocket tester:
YU-3112-C/90890-03112

7-20
 SIGNALING SYSTEM

CHECKING THE COUPLERS AND

LEADS CONNECTION
1. Check: Make sure that a short-circuit does
• Couplers and leads connection not develop between the terminals
Rust/dust/looseness/short-circuit because it may cause damage to
→ Repair or replace. electrical components.
CHECKING THE MULTI-FUNCTION
DISPLAY INPUT VOLTAGE
1. Disconnect the multi-function dis-
play coupler.
2. Set the main switch to "ON".
3. Measure:
• Multi-function display input volt-
age
Out of specification → Replace CHECKING THE SPEED SENSOR
wire harness. OUTPUT VOLTAGE
Tester (+) lead → Brown lead "1" 1. Insert the thin electric conductors
Tester (-) lead → Black lead "2" "1" (lead) into the speed sensor
coupler "2", as shown, and con-
Multi-func- nect the tester to them.
Tester se-
tion dis-
lector posi- Tester (+) lead → White lead "3"
play input
tion Tester (-) lead → Black lead "4"
voltage
10 V or
DCV-20
more • Do not insert the electric conduc-
tors more than required because
it may reduce the waterproof
Make sure that a short-circuit does function of the coupler.
not develop between the terminals • Make sure that a short-circuit
because it may cause damage to does not develop between the
electrical components. terminals because it may cause
damage to electrical compo-
nents.

CHECKING THE MULTI-FUNCTION

DISPLAY OUTPUT VOLTAGE
1. Disconnect the multi-function dis- 2. Set the main switch to "ON".
play coupler. 3. Measure:
2. Set the main switch to "ON". • Speed sensor output voltage
3. Measure: Output voltage not correct → Re-
• Multi-function display output volt- place the speed sensor.
age
Out of specification → Replace
Measurement steps:
multi-function display.
a. Elevate the front wheel and slowly
Tester (+) lead → Red lead "1" rotate it.
Tester (-) lead → Black/White lead b. Measure the voltage (DCV) of
"2" white lead and black lead. With
each full rotation of the front
Multi-func-
Tester se- wheel, the voltage reading should
tion dis-
lector posi- cycle from 0.6 V to 4.8 V to 0.6 V
play output
tion to 4.8 V.
voltage
4.5 V or
DCV-20
more

7-21
PRINTED ON RECYCLED PAPER PRINTED IN JAPAN
(E)