Regulations on Electric Bicycles in Japan
April 1, 2001
Masatoku Kokayu
Officer, PAS Business Department, Yamaha Motor Co., Ltd.
Chairman, (Japan) Conference of Safety Popularization for Electric Assist Bicycles
I. Legal Standards Related to Electric Bicycles in Japan
Standards related to electric bicycles in Japan are established based on the “Road
Traffic Law” under the jurisdiction of the Police Administration. The full text of
related laws is as follows:
11-2, Article 2, the Road Traffic Law (Definition)
“Bicycles” means vehicles with more than two wheels that use pedals or hand
grabs and run through human energy (excluding those running on
rails), other than wheelchairs, walk assist vehicles, etc. for the
handicapped and vehicles for children, and use prime movers to
assist human energy (including those consistent with standards
established in Primer Minister’s Office Order).
3, Article 1, the Implementation Rules for the Road Traffic Law (the Prime Minister’s
Office Order)
Standards established in the Prime Minister’s Office Order of 2, No. 11, Item 1,
Article 2, Standard Law of Bicycles Using Prime Movers to Assist Human
Energy are described as follows:
1. Prime movers used for assisting human energy are those that match
any of the following conditions.
A. Motors.
B. To let bicycles run in the speed less than 24km/h, prime movers are
used for assisting human energy and the rate of assistant power is
respectively the value established in (1) or (2) corresponding to the
speed differentiation described in (1) or (2).
(1) Speed less than 15km/h
(2) Speed over 15km/h and less than 24km/h
First, subtracting 15 from the value of running speed shown in
km/h; then, dividing the result with 9; and finally, subtracting
the result from 1.
X = [speed (km/h) 15] 9
C. To let bicycles run in the speed over 24km/h, prime movers are
used without adding assistant power.
D. Prime movers consistent with any from A to C are of the structure
that cannot be easily modified to those inconsistent with any from
A to C.
2. The function that uses prime movers to assist human energy works
smoothly and the smooth working of the function is to ensure
complete service and avoid occurrence of hindrances.
II. Explanations Related to Laws in Japan
1. Relation between Assist Rate and Speed
3, Article 1, the Implementation Rules for the Road Traffic Law (Prime
Minister’s Office Order)
B and C of Standard 1 for bicycles that use prime movers to assist human
energy (hereinafter referred to as “assist rate”) are shown with graphics as
follows:
Assist Rate
Human Energy Ratio
Motor Power Ratio
Running Speed
1) In speed less than 15km/h, the assist rate is below 1:1.
2) In the speed range over 15km/h and less than 24km/h, the assist rate
reduces in contrast as speed increases while in speed over 24km/h, motor
power becomes zero.
2. General Understandings Regarding the Basis of Standard Values
Regarding the relation between assist rate and speed, though the basis of the
established standard values remain unclear, it is assumed that the values
established in JIS – common speed of practical bicycles = 15km/h and
common speed of sport bicycles = 24km/h are the bases.
Moreover, it is understood that setting the assist rate below 1:1 in maximum
is due to the fact that it is deemed necessary for vehicles to use human energy
as the main driving force to be dealt with as bicycles.
It is understood that the purpose of reducing assist rate in the high-speed
range is to suppress the running speed from becoming too high, then
preventing sudden and dramatic changes in driving force at the point of
24km/h.
These performance standards are determined by investigating the actual
conditions of bicycle utilization and road traffic environments, etc. in the
country and continue to have strong impacts on the unique road
environments in Japan such as generally narrow road space, bicycles sharing
sidewalks with pedestrians, etc.
Regarding the highest speed and assist rate, it is important to establish
standards suitable for traffic environments in different countries.
3. Regarding Battery and Motor Outputs
In Japan, there are no legal standards regarding battery and motor outputs. It
is understood that this is due to the fact that motor assist rate and ceiling
speed are already established and battery output is not likely to rise without
due cause.
III. Model Authorization System
In Japan, model authorization is being carried out by the National Public Safety
Commission in order to ensure that electric assist bicycles comply with legal
standards.
Items to be examined during model authorization are summarized as
follows:
(1) Designs and performance that are established as common bicycles.
(2) Designs and performance that are established as electric assist bicycles.
Testing results of assist rates are presented by public examination
institutes.
(3) Consistency in manufacture of products
Clarify quality control systems, etc.
(4) Structure that cannot be easily modified
Definition of Assist Rate
_ = (P2 P1) P1
_: rate of drive assist power
P1: crank revolving output (watt)
P2: drive output after vehicle correct
The assist rate test corrects the loss horsepower, etc. as it uses chassis dynamo.
III. Issues and Movements of Regulations on Electric Assist Bicycles in Japan
(1) Necessity for improving safety and convenience.
(2) Review from the perspective of universal design in the aging society.
(3) Review on regulations corresponding to new technological renovations
Engine Hybrid Type
Fuel Battery, etc.
(4) Global harmonization of regulations
ISO specification
(5) Battery standardization
