GOVT.

OF KERALA
DEPARTMENT OF TECHNICAL EDUCATION

RAJIV GANDHI INSTITUTE OF TECHNOLOGY

GOVERNMENT
VERNMENT ENGINEERING COLLEGE
KOTTAYAM– 686 501

SEMINAR REPORT
ON

REVIEW OF ALTRNATE
ALTRNATE HUB CENTRE
STEERING DESIGNS IN MOTOR CYCLES
SUBMITTED BY

SUDHEESH KUMAR.E
REGISTER NO: 10013707

DEPARTMENT OF MECHANICAL ENGINEERING

2010-2014
 DEPARTMENT OF MECHANICAL ENGINEERING

RAJIV GANDHI INSTITUTE OF TECHNOLOGY

GOVERNMENT ENGINEERING COLLEGE
KOTTAYAM– 686 501

Certificate
This is to certify
y that the report entitled “REVIEW
REVIEW OF ALTRNATE HUB

CYCLES is a bonafide record of

CENTRE STEERING DESIGNS IN MOTOR CYCLES”

Graduate Seminar presented by SUDHEESH KUMAR.E, 10013707, during the

Reg.No:10013707

year 2013-2014. This report is submitted to Mahatma Gandhi University,

U sity, Kottayam in

partial fulfilment
lment of the requirements for the award of the degree of Bachelor of Technology

in Mechanical Engineering.

ANTONY J. K. CIBY THOMAS

Assistant Professor Professor and HOD
Dept. of Mechanical Engineering Dept. of Mechanical Engineering
RIT, Kottayam RIT, Kottayam
(Staff Coordinator)
 REVIEW OF ALTRNATE HUB CENTRE STEERING DESIGNS IN MOTOR CYCLES

ACKNOWLEDGEMENT

I am very thankful to Antony J.K., (Assistant Professor, ME Dept. RIT) for his

careful guidance and warm support throughout the seminar work. His suggestions have

helped this work take its existing form.

I would like to thank Ciby Thomas, the Head of the Mechanical Engineering

Department, RIT Kottayam, and Dr. K. P. Indiradevi, the Principal, RIT Kottayam for

providing the facilities and the right atmosphere for doing this work.

I express my gratitude towards Manoj Kumar M. and Sajumon K. T. (Assistant

Professors, ME Dept. RIT) and other staff members of our department for their advices and

encouragement. I appreciate the service of the management and the staff of the college.

I give thanks to my friends and family, for assistance and inspiration.

Sudheesh Kumar E

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 REVIEW OF ALTRNATE HUB CENTRE STEERING DESIGNS IN MOTOR CYCLES

ABSTRACT

As motorcycles becomes faster and heavier the need for safety become exponentially

important. Hub centre steering is a technology developed to improve the safety of

motorcycles. The two most significant problems facing current front fork suspensions are

lateral wheel displacement and extremely limited front wheel braking force. Hub centre

steering is designed to eliminate both of these problems. As the increase of speed range is

more pronounced in race bikes, the need for increased braking force is also more important

in the same. Therefore the implementation of hub centre steering mechanism is done mainly

in race bikes. This paper aims to review different iterations of hub centre steering

mechanism in motorcycles. Along with that, other alternate front end designs of motorcycles

to overcome the above said problems are also reviewed.

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CONTENTS

TITLE PAGE NO.

1. INTRODUCTION 1

2. BACKGROUND AND OBJECTIVES 2

3. NER-A-CAR 4

4. DIFAZIO DESIGN 5

4.1. DESIGN AND WORKING 6

4.2. STEERING GEOMETRY 6

4.3. MODELS USING DIFAZIO DESIGN 7

5. DESIGN BY ROEL VAN DER HEIDE 12

5.1. DESIGN AND WORKING 12

5.2. STEERING GEOMETRY 14

5.3. MODELS USING VAN DER HEIDE DESIGN 15

6. FOUR BAR STEERING MECHANISM BY TIER MOTORSPORTS 16

7. OTHER ALTERNATE FRONT END DESIGNS 17

7.1. HOSSACK DESIGN 17

7.2. SWING ARM SUSPENSION SYSTEM 19

7.3. FRONT END STUB AXLE STEERING 20

8. CONCLUSION 21

9. REFERENCES 22

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LIST OF FIGURES
FIGURE NO. DESCRIPTION PAGE NO.

FIGURE 1 problems of conventional steering system. 3

FIGURE 2 Objective of hub centre steering 3

FIGURE 3 Ner-A-Car 4

FIGURE 4 Difazio design 5

FIGURE 5 Steering geometry of Difazio design. 7

FIGURE 6 Hub center steering kit from ISR 8

FIGURE 7 BMW Harier 9

FIGURE 8 Vyrus 987 c3 4vv 11

FIGURE 9 Van Der Heide disign 12

FIGURE 10 Steering geometry of Van Der Heide desig 15

FIGURE 11 Zippelin Broad tracker 16

FIGURE 12 Schematic diagram of steering kit from Tier 17

FIGURE 13 Hossack suspension system 18

FIGURE 14 Schematic diagram of swing arm suspension system 19

FIGURE 15 Stub axle steering in BMW Demonstrator 20

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Chapter 1
INTRODUCTION

The concept of Hub center steering has been around since the early 1900’s and was

first produced by Ner-A-Car. The Ner-A-Car was made under license by the Simplex Luxury

Car maker in Sheffield, England. The company lasted from 1921 to 1926 and went out of

business due to lack of popularity. By the early 1950’s hydraulically damped telescopic fork

suspensions for motorcycles were becoming the standard. This was mostly due to improved

ride over the un-damped systems used for hub center steering. Although telescopic

suspensions were gaining popularity and were very commonly used, this type of steering

systems was not without its own drawbacks. This draw backs lead to development of wide

variety of alternate front end designs after 1950’s.The concept hub centre steering was the

back bone of all that designs. The developers of such steering mechanisms were mainly

custom bike manufacturers. The developments of such systems are still going on all over the

world and the large scale luxury bike manufacturers like BMW are also started taking

interest in this area. This gives the signs that more optimized designs will emerge in near

future so that there will be a revolution in handling and performance of heavy motorcycles

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Chapter 2

BACKGROUND AND OBJECTIVES

Although telescopic front fork suspensions were gaining popularity and were very

commonly used, this type of steering system was not without its own drawbacks. These

drawbacks are exponentially increased as motorcycles get heavier and faster. The most

dangerous draw back to a telescopic front fork is lateral flex in the fork legs which will

cause the tire patch in contact with the ground to move away from the steering axis (lateral

wheel displacement), as seen in figure 1. This can cause the tire to wobble and the operator

to lose control. The second most dangerous drawback to a telescopic front fork suspension

is the force exerted at the steering head of the motorcycle while braking, also see figure 1.

This force will cause the steering head to become heavier during braking and while riding

over a road with hump or irregular projections. Not only does this require a larger frame to

resist these forces, but these forces can cause a moment around the wheel and cause the

motorcycle to flip over itself and injure and sometimes kill the operator. Not only during

braking, but also during cornering, the performance of traditional front fork suspension-

steering system is unsatisfactory. The lateral wheel flexing will come into action also while

taking turns with smaller radius of curvature. Another drawback of telescopic front end is

unbalanced moment in fore and aft plane will cause diving nose effect during braking.

With the rise in popularity in motor cycles and the acknowledged problems of a

telescopic front fork suspension, new design of front end to overcome these problems

became necessary to attain better performance for motorcycles, especially for race bikes.

The concept of hub center steering was the backbone of all such designs.

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fig . 1 – problems of conventional steering system.

The main objectives of hub centre steering systems are the following

• To avoid lateral wheel displacement.

• To increase allowable frond wheel braking power.

• To make steering and suspension independent of each other.

fig. 2 – Objective of hub centre steering

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Chapter 3

NER-A-CAR

Most likely the first attempt at utilizing hub center steering. The Ner-A-Car was

Designed by American Carl Neracher during World War 1 (WW1) with a seven year

production run from 1921 to 1928. The Ner-A-Car was manufactured in England and the

United States of America. It is estimated that around 16,000 Ner-A-Cars were produced and

about 100 remain today. The last recorded sale of a Ner-A-Car was at a Dutc h vintage

motorcycle dealer that sold the Ner-A-Car for $16,000.00 (US currency). The hub center

steering system utilized on this vehicle seems similar to the Difazio design although it was

patented in 1919, 49 years before Difazio’s design was patented. In this design, the

suspension system used was a wishbone type suspension. A close up of the design can be

seen in figure 3. This vehicle was very slow and bulky and hence the performance of hub

centered steering mechanism was not satisfactory in NER-A-CAR.

Fig. 3– Ner-A-Car

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Chapter 4

DIFAZIO DESIGN

British designer Jack Difazio designed a hub center steering system in 1968. This

design is the base of most of the hub center steering systems. The drawing of this Design is

shown inn figure 4.

It has the following draw backs

• It requires large bearings which are expensive and difficult to manufacture.

• When a lateral force is acted on the tire, (for example when hit by a bump on one

side of the tire the king pin may undergo sideward stress and this will cause the

bending of the king pin into S shape.

• This design is impractical in bicycles due to low speed and weight.

Fig.4-Difazio design

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4.1 DESIGN AND WORKING

A large bearing is used and supported in the center by large A frame braces. The A

frame braces holds wheel axle at one end and the other end is hinged to the chase. The

axle supports a vertical king pin which in turn support the wheel hub which can rotate

about the diameter along the king pin. The large bearing is connected to the hub. This

bearing supports wheel. The suspension springs are connected to the above mentioned A

frame and steering control is connected to the hub through a linkage which can absorb any

vertical shock. Hence the suspension and steering systems are independent of each other.

This is shown in figure 4 and 5 in detail.

4.2 STEERING GEOMETRY

The steering geometry of Difazio design is shown in figure 3. Here the king pin

central line is the steering axis and is almost vertical. Therefore the line joining the central

of wheel and the ground coincides with the steering axis and hence makes zero angle with

the same. This results in zero rake angle. The point of intersection of steering axis with the

ground is also same as the point of contact of tier with the ground that is the trail is also

zero (even though the trail and rake angle are zero theoretically, in actual case there will be

a very small rake angle and trail in order to have required directional stability). As the trail

is negligible, there will be maximum response to the steering inputs that is dynamism is

very high or steering head is highly sensitive. Another feature of this design is decreased

directional stability due to decreased rake angle.

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Fig.5-steering geometry of Difazio design

4.3 MODELS USING DIFAZIO DESIGN

4.3.1 STEERING KIT FROM ISR

ISR is a Swedish company started on 1968 mainly to produce brake related products

and they are the first company to produce a universal hub center steering kit which could fit

into any motor cycle. In this kit, an altered Difazio design is used. The main frame support

element is bolted to a central bearing at the central line of the wheel and the Steering

controls are connected directly to the hub. The steering control is through flexible cable so

that any type of shock is absorbed. To introduce this steering kit into a motorcycle, the front

end should be completely custom build. The installation of ISR kit is very expensive to set

up (A cheapest setting will cost around $6700).

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Fig.6-hub centre steering kit from ISR

4.3.2 STELLEN EGELAND’S BMW HARRIER

It is the first motorcycle to utilize ISR kit. The result of testing of this custom bike was

excellent and it became the first proof that hub center steering is practical and can be

successfully employed to get better performance. The survey on this model gave confidence

for ISR to mass produce the hub center steering kit. This model is created from BMW

R1200s by Stellen Egeland of SE services in Europe. Small alternations are made in the

chassis like the engine is lowered to lower center of gravity and hence to increase the

stability.

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Fig.7-BMW Harrier

4.3.3 HONDA ELF

This hub center steered model is made from Honda Rsc1000cc motorcycle for racing.

It uses hub center steering with swing arm support at one end only. This project was first

started Andre De Condranze and Renault marketing boss Francoise Guiter with Yamaha

TZ750 which was very unreliable and under powered. It had many problems, the chassis was

unreliable and many improvements lead to Honda ELF 5 which used Honda RSC Endurance

engine. Honda ELF 5 won the 11th place in 500cc world championship in 1988 and this

encouraged more researches in the field of hub center steering. This project is stopped due to

high expense.

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4.3.4 CHIQANE

It is a Dutch motorcycle company established in 1999 and specialized in custom hub

Centre steering motorcycles and currently one of the potential producers of this type of

bikes. Most of their models have swing arms and brake callipers on both sides. This is also

a proof that there is a market for hub center steering bikes.

4.3.5 BIMOTA TESI 2D AND TESI 3D

Bimota is an Italian company producing hub center steered bikes established in 1990.

Tesi 2D is a joint venture b/w Vyrus,VDM and Bimota and is designed by Rodrigo Ascanio.

Tesi 3D started in 2006 and still active in market. The 2013 model of Tesi 3D costs $37000.

4.3.6 VYRUS 984,985,986 AND 987

Vyrus is an Italian company producing most power full hub center steered bikes. This

company started in 2001 and they mainly uses Ducati engines in their models.Bimta designer

Rodrigo Ascanio is the main designer of Vyrus also. Upto2011 Vyrus bikes have won 11

races, 2 lap records and second place in UK thunder bike championship. It’s latest version

Vyrus 986 M2 won The best contemporary motorcycle trophy at festivals of speed event at

Island Florida. In 985, single sided steering control linkage is used and in 986 models,

double armed fork is used to steering control. Vyrus tried to combine other modern

innovations along with hub center steering in their models. Vyrus 986 m2 is the first bike

using push rod suspension. Costs around $67000. Vyrus 987 C34VV is one of the world’s

most powerful bikes. In this model, 211 HP 1198 CC Ducati supercharged engine is used. It

costs $91000. The victory of Vyrus bikes is best example of increasing popularity of this

technology.

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Fig.8-Vyrus 987c3 4vv

4.3.7 GG DUETTO SIDE CAR

It is a fully assembled side car using BMWk1100S engine manufactured by Swiss

manufacturer GG during 1994-99. Front suspension single sided swing arm and steering is

hub center steering.

4.3.8 BMW K1200S SIDE CAR

Production started in 2006 with a 1200cc engine. There are BMW bikes and side cars

using this engine, the bike uses Duolever suspension and the side car uses single sided swing

arm suspension and hub center steering.

4.3.9 OUSTOURE SUPER NAKED (CONCEPT MODEL)

It is a motorcycle design by Iranian designer Muhammed Raza Shojaie. In this design

shaft drive dual differentials, two wheel drive and hub centre steering systems are combined.

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Chapter 5

DESIGN BY ROEL VAN DER HEIDE

This design is still under progress and is a direct design response to ISR kit. This is

designed by Dutch designer Roel Van Der Heide.

5.1 DESIGN AND WORKING

Fig.9-Van Der Heide dsign

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The invention provides a motorcycle With hub steering, the axle of the hub being

fixedly connected to first support arms and being disposed in such a manner that it can

turn With respect to the hub body. Second support arms are arranged in such a manner that

the front pivot points and rear pivot points lie on non-parallel lines. Attaching the front

wheel in this Way results in an improved suspension and increased stability of a motorcycle

with hub Steering.

The hub center steering by Difazio comprises a front Wheel axle fixedly held

between brackets, the axle holding a king pin onto which a hub body is pivoted. The hub

body supports roller bearings on which the front Wheel can rotate. The brackets are

pivotably connected to two pairs of upper and lower links, one of Which is connected to a

shock absorber, thus providing a parallelogram type suspension for the front wheel. All

of the links are of equal length, and the front lower and upper pivot points lie in a straight

vertical line above one another. The rear lower and upper pivot points also lie in a straight

vertical line above one another. Furthermore the king pin around which the hub body can

turn intersects the centre axis of the axle. A drawback of the hub steering according to

Difazio is that its steering sensitivity is poor and unfavourable. The feeling of control over

the steering is bad. There is a very disadvantageous bump steering effect. The distance

between the turning axis of the hub body and the centre axis of the axle is Zero, resulting

in the front Wheel having no castor. This also makes the motorcycle unstable.

The object of the invention is to eliminate the above and other drawbacks of the

prior art and to provide a motorcycle which allows What is known as hub steering With

considerably improved driving characteristics. Furthermore, the invention aims to provide

a motorcycle with improved stability. According to the invention this object is achieved by

a motorcycle having hub steering, comprising a frame, a front Wheel, a rear Wheel and

an engine, in Which a front line Which joins the lower and upper front pivot points,

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and a rear line Which joins the lower and upper rear pivot points, intersect one another

at a point Which lies above the support arms, in Which the turning axis and the centre

axis of the axle are situated at a distance from one another, and in Which there is a

resilient steering connection between handle bars and the front Wheel. By providing two

sets of upper and lower support arms, preferably above and approximately parallel to the

first support arms, it is possible to achieve greater stability of the motorcycle. Designing the

support arms in such a manner that the pivot points do not lie on parallel lines, but rather on

intersecting lines, results in a highly advantageous steering sensitivity during

compression. The distance between the turning axis of the hub body and the centre axis of

the axle provides for an advantageous castor. During inward springing With Which the

front Wheel moves upwardly With respect to the motor frame, the specific positions of the

pivot points With respect to each other, in combination With the distance between the

turning axis of the hub body and the centre axis of the axle, results in a specific path of

change of the angle of the turning axis in combination With the amount of castor. That is to

say the steering sensitivity changes during inward springing such, that it will be more easier

to steer the motorcycle.

The hub (3) can turn around turning axle (4) on block (5) which is permanently

connected to the axle (2) by shrink fit. It uses front fork to steer.

5.2 STEERING GEOMETRY

Front and back pivot points of swing arms are in non parallel lines and hence

advantageous castor is available. As castor and trail increases directional stability, this type

of steering mechanism provides better directional stability. The steering geometry is shown

in figure. Absence of vertical stresses on the king pin and hence the absence of bending of

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king pin is another advantage of this design. Same time the design is very complex and

expensive.

Fig.10-steering geometry of Van Der Heide design

5.3 MODELS USING VAN DER HEIDE DESIGN

5.3.1 ZIPPELIN BOARDTRACKER

Zippelin Broadtracker is a motorcycle under development by Zippelin works which is a

daughter company of Chiqane. This bike is powered by a HarleyDavidson engine. Van Der

Heide front end steering system is employed.

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Fig.11-zippelin broad tracker

5.3.2 CHIQANE POWERED BY DUCATI

It is also a concept model under development, based on Van Der Heide design.

Here also front fork is used to steer but avoid it acting as a lever during braking.

Chapter 6
FOUR BAR STEERING MECHANISM BY TIER MOTORSPORTS

It is another Design response to the ISR kit by Tier Motorsports and is under

development They first attached this kit with Yamaha R1. In this iteration of hub center

steering, four bar tilting mechanism is used instead of pivot pin. The wheel pivot is on

perfectly vertical axis.

The following sketch is a horizontal cross section cutting the front wheel right above

the Four-Bar Steering Mechanism and looking down at it. It shows how the "virtual steering

axis" is found by extending a line going through the follower links. Where the lines meet is

the point "C" to which the wheel will steer about. This allows the use of a much smaller

wheel hub to achieve the benefits of a vertical steering axis.

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Fig.12-schematic diagram of steering kit from Tier.

Custom steering trail is the main advantage of this design trail is set by 2 spacers that

can be replaced in minutes. Trail being the key value controlling handling characteristics

now let the user choose the right value to match the road condition and their riding style

(lower = more aggressive; higher = more stable).

Chapter 7

OTHER ALTERNATE FRONT END DESIGNS

7.1 HOSSACK DESIGN

It is designed by Norman Hossack. Steering and suspension are independent in this

design. The leverage action during braking is avoided here. This design is used in Britten

V1000 and BMW K1200s. This design does not avoid lateral wheel displacement.

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Fig.13-Hossack suspension system

7.1.1 BRITTEN V1000

Designed in 1991 by John Britten, the Britten V1000 figure 4 (3) utilizes a double

wishbone girder type front suspension and has a carbon fiber frameless chassis. In 1992 the

V1000 won the Dutch round of the Battle of The Twins, and in 1994 the Daytona round. In

between those victories, the V1000 set four motor cycle world speed records: the standing

start quarter mile, mile, and kilometer, and lastly the flying mile at 302 kph (187.7 Mph). In

1995 John Britten died of cancer and development of the Britten V1000 stopped. Although

this is not a hub center steering design, it was probably the rejuvenator of the motorcycle

racing worlds desire to go faste r, and realization that a traditional front fork design was

not optimal and a modified version was far superior.

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7.2 SWING ARM SUSPENSION SYSTEM

Fig.14-schematic diagram of swing arm suspension system

This steering system is invented by James G Parker. The connection of swing arm

to the upright is through a universal ball joint. The steering control is done through a steering

column which also helps to absorb shock. This type of steering system is used in Zuzuki

powered GSK-RADD and Yamaha GTS 1000A.

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7.3 FRONT END STUB AXLE STEERING

The recently completed BMW project Demonstrator D1200R utilizes front end stub

axle to steer. In this project a 1200cc boxer engine is used. This design is simpler than

Difazio design but as only one sided support can be used. The main drawback of this system

is difficulty in balancing.

Fig.15-stub axle type frond end in BMW Demonstrator

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Chapter 8

CONCLUSION

Hub center steering system is superior steering system for race bikes as it avoids

wobbling of tier and lateral wheel flexing. The increased sensitivity of steering system and

improved dynamism are also helpful in the case of racing bikes. But this technology is yet to

develop in order to use in ordinary two wheelers. The absence of satisfactory trial and

resulting reduction in directional stability is one challenge in the case of ordinary bikes. The

limitation in turning radius due to inherent design characteristics is also a challenge to be

considered while modifying the system for low speed vehicles. This system is currently very

expensive too.

Even though hub center steering was conceived in 1919, this technology became

popular just recently as a result of the wider market-entry of high-end bikes. Up to now

Difazio is most reputed design but the completion of Van Der Heide project will be a

milestone.

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Chapter 8

REFERENCES

1. Thesis submitted on ‘Hub center steering’ to Mechanical Engineering Technology

Program of the University of Cincinnati 2012.

2. US patent on ‘motorcycle provided with a steering hub’ - Van Der Heide 2000.

3. US patent on ‘front swing arm suspension system’ -James G Parker 1995.

4. US patent on ‘motorcycle having a stub-axle steering’ - Wilhelm K Beirlein 1996.

5. EP0432107 ‘A device for steering the frront wheel’.

6. Britten Motorcycle Company of New Zealand. Britten Motorcycles(online).

7. Motorcycle Handling and Chassis Design: The Art and Science

8. Deconstructing Dynamism in Motorcycle Design(IJMS).

9. The Semantics of Motorcycle Design: A Kansei (IJMS).Engineering Framework (IJMS).

10. Make Today Count: Motorcycling as Memento Mori (IJMS).

11. Design of motor cycle active chassis geometry change system.

12. Advances in the Modeling of Motorcycle Dynamics

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