YAMAHA WR 450F 2008 Owners Manual

6-20
FRONT FORK
8. Install:
• Outer tube "1"
To inner tube "2".
9. Install:
• Slide metal "1"
• Oil seal washer "2"
To outer tube slot.
Press the slide metal into the outer
tube with fork seal driver "3".
10. Install:
• Oil seal "1"
Press the oil seal into the outer tube
with fork seal driver "2".
11. Install:
• Stopper ring "1"
Fit the stopper ring correctly in the
groove in the outer tube.
12. Install:
• Dust seal "1"
Apply the lithium soap base grease
on the inner tube.
13. Check:
• Inner tube smooth movement
Tightness/binding/rough spots →
Repeat the steps 2 to 12.
14. Compress the front fork fully.
15. Fill:
• Front fork oil
Until outer tube top surface with
recommended fork oil "1".
• 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-
formance.
• Never allow foreign materials to
enter the front fork.
16. After filling, pump the damper rod
"1" slowly up and down more than
10 times to distribute the fork oil.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-
ute the fork oil once more.
Be careful not to excessive full stroke.
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.
19. Wait ten minutes until the air bub-
bles have been removed from the
front fork, and the oil has dis-
pense evenly in system before
setting recommended oil level.
Fill with the fork oil up to the top end
of the outer tube, or the fork oil will not
spread over to every part of the front
forks, thus making it impossible to ob-
tain the correct level.
Be sure to fill with the fork oil up to the
top of the outer tube and bleed the
front forks.
20. Measure:
• Oil level (left and right) "a"
Out of specification→Adjust. Fork seal driver:
YM-A0948/90890-01502
Fork seal driver:
YM-A0948/90890-01502
Recommended oil:
Suspension oil "S1"
Standard oil level:
132 mm (5.20 in)
*125 mm (4.92 in)
Extent of adjustment:
95–150 mm (3.74–5.91
in)
From top of outer tube
with inner tube and
damper rod "1" fully
compressed without
spring.
* For AUS, NZ, ZA and EUROPE

6-21
FRONT FORK
Be sure to install the spring guide "2"
when checking the oil level.
Never fail to make the oil level ad-
justment between the maximum
and minimum level and always ad-
just each front fork to the same
setting. Uneven adjustment can
cause poor handling and loss of
stability.
21. Measure:
• Distance "a"
Out of specification→Turn into
the locknut.
22. Loosen:
• Rebound damping adjuster "1"
• Loosen the rebound damping ad-
juster finger tight.
• Record the set position of the ad-
juster (the amount of turning out the
fully turned in posi-tion).
23. Install:
• Push rod "1"
• Fork spring "2"
• Install the fork spring with the
damper rod "3" pulled up.
• After installing the fork spring, hold
the damper rod end so that it will not
go down.
24. Install:
• Spring seat "1"
• Front fork cap bolt "2"
Fully finger tighten the front fork cap
bolt onto the damper rod.
25. Tighten:
• Front fork cap bolt (locknut) "1"
Hold the locknut "2" and tighten the
front fork cap bolt with specified
torque.
26. Install:
• Front fork cap bolt "1"
To outer tube.
Temporarily tighten the cap bolt.
27. Install:
• Protector guide "1"
Install the protector guide with its wid-
er side "a" facing downward.
INSTALLING THE FRONT FORK
1. Install:
• Front fork "1"
• Temporarily tighten the pinch bolts
(lower bracket).
• Do not tighten the pinch bolts (up-
per bracket) yet.
2. Tighten:
• Front fork cap bolt Distance "a":
18 mm (0.71 in) or more
Between damper rod
"1" top and locknut "2"
top.
Front fork cap bolt (lock-
nut):
29 Nm (2.9 m•kg, 21
ft•lb)
Front fork cap bolt:
30 Nm (3.0 m•kg, 22
ft•lb)

6-22
FRONT FORK
3. Adjust:
• Front fork top end "a"
4. Tighten:
• Pinch bolt (upper bracket) "1"
• Pinch bolt (lower bracket) "2"
Tighten the lower bracket to speci-
fied torque. If torqued too much, it
may cause the front fork to mal-
function.
5. Install:
• Speed sensor lead "1"
• Plate 1 "2"
• Bolt (plate 1) "3"
To right protector "4".
Install the speed sensor lead so that
its paint "a" directs as shown and
align the bottom "b" of the plate 1 with
the same paint.
6. Install:
• Speed sensor lead "1"
•Plate 2 "2"
• Screw (plate 2) "3"
To right protector "4".
Install the plate 2 in the direction as
shown.
7. Install:
• Protector "1"
• Bolt (protector) "2"
8. Adjust:
• Rebound damping force
Turn in the damping adjuster "1" fin-
ger-tight and then turn out to the orig-
inally set position.
Front fork top end (stan-
dard) "a":
Zero mm (Zero in)
Pinch bolt (upper brack-
et):
21 Nm (2.1 m•kg, 15
ft•lb)
Pinch bolt (lower brack-
et):
21 Nm (2.1 m•kg, 15
ft•lb)
Bolt (plate 1):
4 Nm (0.4 m•kg, 2.9 ft •
lb)
Screw (plate 2):
0.5 Nm (0.05 m•kg, 0.36
ft•lb)
Bolt (protector):
7 Nm (0.7 m•kg, 5.1
ft•lb)

6-23
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

6-24
HANDLEBAR
REMOVING THE BRAKE MASTER
CYLINDER
1. Remove:
• Brake master cylinder bracket "1"
• Brake master cylinder "2"
• Do not let the brake master cylin-
der hang on the brake hose.
• Keep the brake master cylinder
cap side horizontal to prevent air
from coming in.
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.
CHECKING THE HANDLEBAR
1. Inspect:
• Handlebar "1"
Bends/cracks/damage→Re-
place.
Do not attempt to straighten a bent
handlebar as this may dangerous-
ly weaken the handlebar.
INSTALLING THE HANDLEBAR
1. Install:
• Handlebar lower holder "1"
• Washer "2"
• Nut (handlebar lower holder) "3"
• Install the handlebar lower holder
with its side having the greater dis-
tance "a" from the mounting bolt
center facing forward.
• Apply the lithium soap base grease
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.
2. Install:
• Handlebar "1"
• Handlebar upper holder "2"
• Bolt (handlebar upper holder) "3"
• 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.
• Install the handlebar so that the pro-
jection "c" of the handlebar upper
holder is positioned at the mark on
the handlebar as shown.
• First tighten the bolts on the front
side of the handlebar upper holder,
and then tighten the bolts on the
rear side.
3. Tighten:
• Nut (handlebar lower holder) "1"
4. Install:
• Left grip "1"
Apply the adhesive to the handle-
bar "2".
• Before applying the adhesive, wipe
off grease or oil on the handlebar
surface "a" with a lacquer thinner.
• Install the left grip to the handlebar
so that the line "b" between the two
arrow marks faces straight upward.
Bolt (handlebar upper
holder):
28 Nm (2.8 m•kg, 20
ft•lb)
Nut (handlebar lower
holder):
34 Nm (3.4 m•kg, 24
ft•lb)

6-25
HANDLEBAR
5. Install:
• Right grip "1"
•Collar "2"
Apply the adhesive on the tube
guide "3".
• Before applying the adhesive, wipe
off grease or oil on the tube guide
surface "a" with a lacquer thinner.
• Install the grip to the tube guide so
that the grip match mark "b" and
tube guide slot "c" form the angle as
shown.
6. Install:
• Grip cap cover "1"
• Throttle grip "2"
Apply the lithium soap base grease
on the throttle grip sliding surface.
7. Install:
• Throttle cables "1"
To tube guide "2".
Apply the lithium soap base grease
on the throttle cable end and tube
guide cable winding portion.
8. Install:
• Throttle cable cap "1"
• Screw (throttle cable cap) "2"
After tightening the screws, check
that the throttle grip "3" moves
smoothly. If it does not, retighten
the bolts for adjustment.
9. Install:
• Grip cap cover "1"
• Cover (throttle cable cap) "2"
10. Install:
• Start switch "1"
• Brake master cylinder "2"
• Brake master cylinder bracket "3"
• Bolt (brake master cylinder brack-
et) "4"
•Clamp "5"
• The start switch and brake master
cylinder bracket should be installed
according to the dimensions
shown.
• Install the bracket so that the arrow
mark "a" faces upward.
• First tighten the bolt on the upper
side of the brake master cylinder
bracket, and then tighten the bolt on
the lower side.
11. Install:
• Engine stop switch "1"
• Clutch lever holder "2"
• Bolt (clutch lever holder) "3"
• Hot starter lever holder "4"
• Bolt (hot starter lever holder) "5"
• Clamp "6"
• 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.
Screw (throttle cable
cap):
4 Nm (0.4 m•kg, 2.9
ft•lb)
Bolt (brake master cylin-
der bracket):
9 Nm (0.9 m•kg, 6.5
ft•lb)
Bolt (clutch lever holder):
4 Nm (0.4 m•kg, 2.9
ft•lb)
Bolt (hot starter lever
holder):
4 Nm (0.4 m•kg, 2.9
ft•lb)

6-26
HANDLEBAR
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 CABLE 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.

6-27
STEERING
STEERING
REMOVING THE STEERING
Order Part name Q'ty Remarks
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
under the engine.Refer to "HANDLING NOTE".
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.
8 Lower bracket 1

6-28
STEERING
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. Order Part name Q'ty Remarks

6-29
STEERING
HANDLING NOTE
Support the machine securely so
there is no danger of it falling over.
REMOVING THE STEERING RING
NUT
1. Remove:
• Steering ring nut "1"
Use the steering nut wrench "2".
Support the steering stem so that
it may not fall down.
REMOVING THE LOWER
BEARING
1. Remove:
• Lower bearing "1"
Use the floor chisel "2".
Take care not to damage the steer-
ing shaft thread.
REMOVING THE BEARING RACE
1. Remove:
• Bearing race "1"
Remove the bearing race using
long rod "2" and the hammer.CHECKING THE STEERING STEM
1. Inspect:
• Steering stem "1"
Bend/damage→Replace.
CHECKING THE BEARING AND
BEARING RACE
1. Wash the bearings and bearing
races with a solvent.
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
smooth in their operation in the
bearing races, replace bearings
and bearing races as a set.
INSTALLING THE LOWER
BRACKET
1. Install:
• Lower bearing "1"
Apply the lithium soap base grease
on the dust seal lip and bearing inner
circumference.
2. Install:
• Bearing race
• Upper bearing "1"
• Bearing race cover "2"
Apply the lithium soap base grease
on the bearing and bearing race cov-
er lip.
3. Install:
• Lower bracket "1"
Apply the lithium soap base grease
on the bearing, the portion "a" and
thread of the steering stem.
4. Install:
• Steering ring nut "1"
Tighten the steering ring nut using
the steering nut wrench "2".
Refer to "CHECKING AND AD-
JUSTING THE STEERING
HEAD" section in the CHAPTER
3.
5. Check the steering stem by turn-
ing it lock to lock. If there is any
binding, remove the steering stem
assembly and inspect the steer-
ing bearings. Steering nut wrench:
YU-33975/90890-01403
Steering ring nut:
7 Nm (0.7 m•kg, 5.1
ft•lb)