
3-22
CHASSIS
ADJUSTING THE FRONT FORK
REBOUND DAMPING FORCE
1. Adjust:
• Rebound damping force
By turning the adjuster "1".
• STANDARD POSITION:
This is the position which is back
by the specific number of clicks
from the fully turned-in position.
Do not force the adjuster past the
minimum or maximum extent of
adjustment. The adjuster may be
damaged.
Always adjust each front fork to
the same setting. Uneven adjust-
ment can cause poor handling and
loss of stability.
ADJUSTING THE FRONT FORK
COMPRESSION DAMPING FORCE
1. Remove:
• Rubber cap
2. Adjust:
• Compression damping force
By turning the adjuster "1".• STANDARD POSITION:
This is the position which is back
by the specific number of clicks
from the fully turned-in position.
Do not force the adjuster past the
minimum or maximum extent of
adjustment. The adjuster may be
damaged.
Always adjust each front fork to
the same setting. Uneven adjust-
ment can cause poor handling and
loss of stability.
3. Install:
• Rubber cap
CHECKING THE REAR SHOCK
ABSORBER
1. Inspect:
• Swingarm smooth action
Abnormal noise/unsmooth action
→Grease the pivoting points or
repair the pivoting points.
Damage/oil leakage→Replace.ADJUSTING THE REAR SHOCK
ABSORBER SPRING PRELOAD
1. Elevate the rear wheel by placing
the suitable stand under the en-
gine.
2. Remove:
• Rear frame
3. Measure:
• Spring fitting length
The I.D. mark "a" is marked at the end
of the spring.
4. Adjust:
• Spring preload
Adjustment steps:
a. Loosen the locknut "1".
b. Loosen the adjuster "2" until there
is some clearance between the
spring and adjuster.
c. Measure the spring free length
"a".
d. Turn the adjuster "2". Stiffer "a" →Increase the re-
bound damping force. (Turn
the adjuster "1" in.)
Softer "b" →Decrease the re-
bound damping force. (Turn
the adjuster "1" out.)
Extent of adjustment:
Maximum Minimum
Fully turned in
position20 clicks out
(from maximum
position)
Standard position:
9 clicks out
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.)
Extent of adjustment:
Maximum Minimum
Fully turned in
position20 clicks out
(from maximum
position)
Standard position:
11 clicks out
Standard fitting length:
I.D. MARK/Q'TY Length
Yellow/1 248.5 mm
(9.78 in)
* 245.0 mm
(9.65 in)
* For AUS, NZ and ZA
Stiffer →Increase the spring pre-
load. (Turn the adjuster "2" in.)
Softer→Decrease the spring pre-
load. (Turn the adjuster "2"
out.)

3-24
CHASSIS
• STANDARD POSITION:
This is the position which is back
by the specific number of turns
from the fully turned-in position.
(Which align the punch mark "a"
on the adjuster with the punch
mark "b" on the adjuster body.)
Do not force the adjuster past the
minimum or maximum extent of
adjustment. The adjuster may be
damaged.
CHECKING THE TIRE PRESSURE
1. Measure:
• Tire pressure
Out of specification→Adjust.
• Check the tire while it is cold.
• Loose bead stoppers allow the tire to
slip off its position on the rim when
the tire pressure is low.
• A tilted tire valve stem indicates that
the tire slips off its position on the rim.
• If the tire valve stem is found tilted,
the tire is considered to be slipping off
its position. Correct the tire position.
CHECKING AND TIGHTENING THE
SPOKES
The following procedure applies to all
of the spokes.
1. Check:
• Spokes
Bend/damage→Replace.
Loose spoke→Retighten.
Tap the spokes with a screw-
driver.
A tight spoke will emit a clear, ringing
tone; a loose spoke will sound flat.
2. Tighten:
• Spokes
(with a spoke nipple wrench "1")
Be sure to tighten the spokes before
and after break-in.
CHECKING THE WHEELS
1. Inspect:
• Wheel runout
Elevate the wheel and turn it.
Abnormal runout→ Replace.2. Inspect:
• Bearing free play
Exist play→Replace.
CHECKING AND ADJUSTING THE
STEERING HEAD
1. Place a stand under the engine to
raise the front wheel off the
ground. WARNING! Securely
support the vehicle so that
there is no danger of it falling
over.
2. Check:
• Steering stem
Grasp the bottom of the forks and
gently rock the fork assembly
back and forth.
Free play→Adjust steering head.
3. Check:
• Steering smooth action
Turn the handlebar lock to lock.
Unsmooth action→Adjust steer-
ing ring nut.
4. Adjust:
• Steering ring nut
Steering ring nut adjustment
steps:
a. Remove the headlight.
b. Remove the handlebar and upper
bracket.
c. Loosen the steering ring nut "1"
using the steering nut wrench "2". Standard position:
1-1/12–1-5/12 turns out
* 1–1-1/3 turns out
* For AUS, NZ and ZA
Standard tire pressure:
100 kPa (1.00 kgf/cm
2,
15 psi)
Spoke nipple wrench:
YM-01521/90890-01521
Spokes:
3 Nm (0.3 m•kg, 2.2
ft•lb)
Steering nut wrench:
YU-A9472/90890-01403

4-5
CHASSIS
CHASSIS
SELECTION OF THE SECONDARY
REDUCTION RATIO (SPROCKET)
• It is generally said that the second-
ary gear ratio should be reduced for
a longer straight portion of a speed
course and should be increased for
a course with many corners. Actual-
ly, however, as the speed depends
on the ground condition of the day
of the ride, be sure to run through
the circuit to set the machine suit-
able for the entire course.
• In actuality, it is very difficult to
achieve settings suitable for the en-
tire course and some settings may
be sacrificed. Thus, the settings
should be matched to the portion of
the course that has the greatest ef-
fect on the ride result. In such a
case, run through the entire course
while making notes of lap times to
find the best balance; then, deter-
mine the secondary reduction ratio.
• If a course has a long straight por-
tion where a machine can run at
maximum speed, the machine is
generally set such that it can devel-
op its maximum revolutions toward
the end of the straight line, with care
taken to avoid the engine over-rev-
ving.
Riding technique varies from rider to
rider and the performance of a ma-
chine also vary from machine to ma-
chine. Therefore, do not imitate other
rider's settings from the beginning but
choose your own setting according to
the level of your riding technique.
DRIVE AND REAR WHEEL
SPROCKETS SETTING PARTS
For EUROPE
For AUS and NZ
For ZATIRE PRESSURE
Tire pressure should be adjust to suit
the road surface condition of the cir-
cuit.
• Under a rainy, muddy, sandy, or
slippery condition, the tire pressure
should be lower for a larger area of
contact with the road surface.
• Under a stony or hard road condi-
tion, the tire pressure should be
higher to prevent a flat tire.
FRONT FORK SETTING
The front fork setting should be made
depending on the rider's feeling of an
actual run and the circuit conditions.
The front fork setting includes the fol-
lowing three factors:
1. Setting of air spring characteris-
tics
• Change the fork oil level.
2. Setting of spring preload
• Change the spring.
• Install the adjustment washer.
3. Setting of damping force
• Change the compression damp-
ing.
• Change the rebound damping.
The spring acts on the load and
the damping force acts on the
cushion travel speed. Secondary reduction ratio =
Number of rear wheel sprocket
teeth/Number of drive sprocket
teeth
Standard secondary
reduction ratio47/14
(3.357)
* 50/13
(3.846)
* For AUS, NZ and ZA
Part
nameSize Part number
Drive
sprocket
"1"
13T 9383B-13218
(STD) 14T 9383B-14222
Rear
wheel
sprocket
"2"
(STD) 47T 1C3-25447-00
48T 5GS-25448-50
50T 5TJ-25450-80
52T 5TJ-25452-80
Part
nameSize Part number
Drive
sprocket
"1"
(STD) 13T 9383B-13218
14T 9383B-14222
Rear
wheel
sprocket
"2"
48T 1C3-25448-00
49T 1C3-25449-00
(STD) 50T 1C3-25450-00
51T 1C3-25451-00
52T 1C3-25452-00
Part
nameSize Part number
Drive
sprocket
"1"
(STD) 13T 9383B-13218
Rear
wheel
sprocket
"2"
48T 5GS-25448-50
(STD) 50T 5TJ-25450-80
52T 5TJ-25452-80
Standard tire pressure:
100 kPa (1.00 kgf/cm2,
15 psi)
Extent of adjustment:
60–80 kPa (0.60–0.80
kgf/cm
2, 9.0–12 psi)
Extent of adjustment:
100–120 kPa (1.00–1.20
kgf/cm
2, 15–18 psi)

4-7
CHASSIS
REAR SUSPENSION SETTING
The rear suspension setting should
be made depending on the rider's
feeling of an actual run and the circuit
conditions.
The rear suspension setting includes
the following two factors:
1. Setting of spring preload
• Change the set length of the
spring.
• Change the spring.
2. Setting of damping force
• Change the rebound damping.
• Change the compression damp-
ing.
CHOOSING SET LENGTH
1. Place a stand or block under the
engine to put the rear wheel
above the floor, and measure the
length "a" between the rear wheel
axle center and the rear fender
holding bolt.
2. Remove the stand or block from
the engine and with a rider astride
the seat, measure the sunken
length "b" between the rear wheel
axle center and the rear fender
holding bolt.3. Loosen the locknut "1" and make
adjustment by turning the spring
adjuster "2" to achieve the stan-
dard figure from the subtraction of
the length "b" from the length "a".
• If the machine is new and after it is
broken in, the same set length of
the spring may change because of
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.
SETTING OF SPRING AFTER
REPLACEMENT
After replacement, be sure to adjust
the spring to the set length [sunken
length 90–100 mm (3.5–3.9 in)] and
set it.
1. Use of soft spring
• Set the soft spring for less re-
bound damping to compensate
for its less spring load. Run with
the rebound damping adjuster
one or two clicks on the softer
side and readjust it to suit your
preference.
2. Use of stiff spring
• Set the soft spring for more re-
bound damping to compensate
for its greater spring load. Run
with the rebound damping adjust-
er one or two clicks on the stiffer
side and readjust it to suit your
preference.
Adjusting the rebound damping will
be followed more or less by a change
in the compression damping. For cor-
rection, turn the low compression
damping adjuster on the softer side.
When using a rear shock absorber
other than currently installed, use
the one whose overall length "a"
does not exceed the standard as it
may result in faulty performance.
Never use one whose overall
length is greater than standard.
REAR SHOCK ABSORBER
SETTING PARTS
• Rear shock spring "1"
• The I.D. mark "a" is marked at the
end of the spring.
• Spring specification varies accord-
ing to the color and quantity of I.D.
marks.
Standard figure:
90–100 mm (3.5–3.9 in)
Length "a" of standard
shock:
488.5 mm (19.23 in)
TYPESPRI
NG
RAT
ESPRING
PART
NUM-
BER
(-22212-)I.D.
MARK/
Q'TY
SOFT4.3 5UN-00 Brown/1
4.5 5UN-10 Green/1
4.7 5UN-20 Red/1
4.9 5UN-30 Black/1
5.1 5UN-40 Blue/1
STD 5.3 5UN-50 Yellow/1
STIFF5.5 5UN-60 Pink/1
5.7 5UN-70 White/1

5-44
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

5-46
KICK SHAFT AND SHIFT SHAFT
REMOVING THE KICK SHAFT
ASSEMBLY
1. Remove:
• Kick shaft assembly "1"
Unhook the torsion spring "2" from
the hole "a" in the crankcase.
REMOVING THE SHIFT GUIDE
AND SHIFT LEVER ASSEMBLY
1. Remove:
• Bolt (shift guide)
• Shift guide "1"
• Shift lever assembly "2"
The shift lever assembly is disassem-
bled at the same time as the shift
guide.
REMOVING THE SEGMENT
1. Remove:
• Bolt (segment) "1"
• Segment "2"
Turn the segment counterclockwise
until it stops and loosen the bolt.
If the segment gets an impact, it
may be damaged. Take care not to
give an impact to the segment
when removing the bolt.
CHECKING THE KICK SHAFT AND
RATCHET WHEEL
1. Check:
• Ratchet wheel "1" smooth move-
ment
Unsmooth movement→Replace.
• Kick shaft "2"
Wear/damage→Replace.
• Spring "3"
Broken→Replace.
CHECKING THE KICK GEAR, KICK
IDLE GEAR AND RATCHET
WHEEL
1. Inspect:
• Kick gear "1"
• Kick idle gear "2"
• Ratchet wheel "3"
• Gear teeth "a"
• Ratchet teeth "b"
Wear/damage→Replace.
CHECKING THE SHIFT SHAFT
1. Inspect:
• Shift shaft "1"
Bend/damage→Replace.
• Spring "2"
Broken→Replace.CHECKING THE SHIFT GUIDE AND
SHIFT LEVER ASSEMBLY
1. Inspect:
• Shift guide "1"
• Shift lever "2"
•Pawl "3"
• Pawl pin "4"
• Spring "5"
Wear/damage→Replace.
CHECKING THE STOPPER LEVER
1. Inspect:
• Stopper lever "1"
Wear/damage→Replace.
• Torsion spring "2"
Broken→Replace.
INSTALLING THE SEGMENT
1. Install:
• Segment "1"
• Bolt (segment)
Align the notch "a" on the segment
with the pin "b" on the shift cam.
If the segment gets an impact, it
may be damaged. Take care not to
give an impact to the segment
when tightening the bolt.
Bolt (segment):
30 Nm (3.0 m•kg, 22
ft•lb)

5-47
KICK SHAFT AND SHIFT SHAFT
INSTALLING THE STOPPER
LEVER
1. Install:
• Torsion spring "1"
• Stopper lever "2"
• Bolt (stopper lever) "3"
Align the stopper lever roller with the
slot on segment.
INSTALLING THE SHIFT GUIDE
AND SHIFT LEVER ASSEMBLY
1. Install:
• Spring "1"
• Pawl pin "2"
•Pawl "3"
To shift lever "4".
Apply the engine oil on the spring,
pawl pin and pawl.
2. Install:
• Shift lever assembly "1"
To shift guide "2".3. Install:
• Shift lever assembly "1"
• Shift guide "2"
• The shift lever assembly is installed
at the same time as the shift guide.
• Apply the engine oil on the bolt
(segment) shaft.
4. Install:
• Bolt (shift guide) "1"
INSTALLING THE SHIFT SHAFT
1. Install:
• Roller "1"
• Collar "2"
• Torsion spring "3"
• Shift shaft "4"
Apply the engine oil on the roller and
shift shaft.
2. Install:
• Shift pedal
Refer to "AC MAGNETO AND
STARTER CLUTCH" section.INSTALLING THE KICK SHAFT
ASSEMBLY
1. Install:
• Kick gear "1"
• Washer "2"
• Circlip "3"
• Ratchet wheel "4"
• Spring "5"
• Washer "6"
• Circlip "7"
To kick shaft "8".
• 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
"b" on the kick shaft.
2. Install:
• Torsion spring "1"
To kick shaft "2".
Make sure the stopper "a" of the tor-
sion spring fits into the hole "b" on the
kick shaft.
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
torsion spring.
Bolt (stopper lever):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Bolt (shift guide):
10 Nm (1.0 m•kg, 7.2
ft•lb)

5-48
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.