2004 YAMAHA YZ250LC wheel

3-25
DRIVE CHAIN SLACK ADJUSTMENT
INSP
ADJ
EC36A061
DRIVE CHAIN SLACK ADJUSTMENT
1. Elevate the rear wheel by placing the suit-
able stand under the engine.
2. Check:
9Drive chain slack a
Above the seal guard installation bolt.
Out of specification Adjust
NOTE:
Before checking and/or adjusting, rotate the rear
wheel through several revolutions and check the
slack several times to find the tightest point. Check
and/or adjust chain slack with rear wheel in this
“tight chain” position.
Drive chain slack:
40~50 mm (1.6~2.0 in)
Drive chain lubricant:
SAE 10W-30 motor oil or suitable
chain lubricants
5. Install:
9Drive chain 1
9Joint 2
9Master link clip 3
cC
Be sure to install the master link clip to the
direction as shown.
aTurning direction
6. Lubricate:
9Drive chain
5XF-9-30-3B 5/6/03 6:31 PM Page 14

3-26
FRONT FORK INSPECTION
INSP
ADJ
3. Adjust:
9Drive chain slack
EC36C000
FRONT FORK INSPECTION
1. Inspect:
9Front fork smooth action
Operate the front brake and stroke the
front fork.
Unsmooth action/oil leakage Repair or
replace.
Drive chain slack adjustment steps:
9Loosen the axle nut 1and locknuts 2.
9Adjust chain slack by turning the
adjusters 3.
To tighten Turn adjuster 3 3
counter-
clockwise.
To loosen Turn adjuster 3 3
clockwise
and push wheel forward.
9Turn each adjuster exactly the same amount
to maintain correct axle alignment. (There are
marks aon each side of chain puller align-
ment.)
NOTE:
Turn the adjuster so that the chain is in line
with the sprocket, as viewed from the rear.
cC
Too small chain slack will overload the
engine and other vital parts; keep the
slack within the specified limits.
9Tighten the axle nut while pushing down the
drive chain.
9Tighten the locknuts.
Axle nut:
125 Nm (12.5 m•kg, 90 ft•lb)
Locknut:
16 Nm (1.6 m•kg, 11 ft•lb)
5XF-9-30-3B 5/6/03 6:31 PM Page 16

3-27
FRONT FORK OIL SEAL AND DUST SEAL CLEANING/
FRONT FORK INTERNAL PRESSURE RELIEVING/
FRONT FORK REBOUND DAMPING FORCE ADJUSTMENTINSP
ADJ
EC36D001
FRONT FORK OIL SEAL AND DUST SEAL
CLEANING
1. Remove:
9Protector
9Dust seal 1
NOTE:
Use a thin screw driver, and be careful not to
damage the inner fork tube and dust seal.
2. Clean:
9Dust seal a
9Oil seal b
NOTE:
9Clean the dust seal and oil seal after every run.
9Apply the lithium soap base grease on the in-
ner tube.
EC36H002
FRONT FORK REBOUND DAMPING FORCE
ADJUSTMENT
1. Adjust:
9Rebound damping force
By turning the adjuster 1.
Stiffer a a
Increase the rebound damping
force. (Turn the adjuster 1 1
in.)
Softer b b
Decrease the rebound
damping force. (Turn the
adjuster 1 1
out.)
EC36f000
FRONT FORK INTERNAL PRESSURE
RELIEVING
NOTE:
If the front fork initial movement feels stiff during
a run, relieve the front fork internal pressure.
1. Elevate the front wheel by placing a suitable
stand under the engine.
2. Remove the air bleed screw 1and release
the internal pressure from the front fork.
3. Install:
9Air bleed screw
1 Nm (0.1 m•kg, 0.7 ft•lb)
5XF-9-30-3B 5/6/03 6:31 PM Page 18

3-30
REAR SHOCK ABSORBER SPRING PRELOAD
ADJUSTMENTINSP
ADJ
EC36M014
REAR SHOCK ABSORBER SPRING
PRELOAD ADJUSTMENT
1. Elevate the rear wheel by placing the suit-
able stand under the engine.
2. Remove:
9Rear frame
3. Loosen:
9Locknut 1
4. Adjust:
9Spring preload
By turning the adjuster 2.
NOTE:
9Be sure to remove all dirt and mud from around
the locknut and adjuster before
adjustment.
9The length of the spring (installed) changes 1.5
mm (0.06 in) per turn of the adjuster.
cC
Never attempt to turn the adjuster beyond
the maximum or minimum setting.
5. Tighten:
9Locknut
6. Install:
9Rear frame (upper)
9Rear frame (lower)
Stiffer Increase the spring preload.
(Turn the adjuster 2 2
in.)
Softer Decrease the spring pre-
load. (Turn the adjuster 2 2
out.)
Extent of adjustment
240.5~258.5 mm
(9.47~10.18 in)
*255.5~273.5 mm
(10.06~10.77 in)
Spring length (installed) a a
:
Standard length
245 mm (9.65 in)
*268 mm (10.55 in)
*For EUROPE
32 Nm (3.2 m•kg, 23 ft•lb)
29 Nm (2.9 m•kg, 21 ft•lb)
5XF-9-30-3B 5/6/03 6:31 PM Page 24

3-34
TIRE PRESSURE CHECK/SPOKES INSPECTION AND
TIGHTENING/WHEEL INSPECTIONINSP
ADJ
EC36Q001
TIRE PRESSURE CHECK
1. Measure:
9Tire pressure
Out of specification Adjust.
NOTE:
9Check the tire while it is cold.
9Loose bead stoppers allow the tire to slip off its
position on the rim when the tire pressure is
low.
9A tilted tire valve stem indicates that the tire
slips off its position on the rim.
9If the tire valve stem is found tilted, the tire is
considered to be slipping off its position.
Correct the tire position.
EC36S002
SPOKES INSPECTION AND TIGHTENING
1. Inspect:
9Spokes 1
Bend/Damage Replace.
Loose spoke Retighten.
2. Tighten:
9Spokes
NOTE:
Be sure to retighten these spokes before and af-
ter break-in. After a practice or a race check
spokes for looseness.
EC36T000
WHEEL INSPECTION
1. Inspect:
9Wheel runout
Elevate the wheel and turn it.
Abnormal runout Replace.
Standard tire pressure:
100 kPa (1.0 kgf/cm
2, 15 psi)
3 Nm (0.3 m•kg, 2.2 ft•lb)
5XF-9-30-3B 5/6/03 6:32 PM Page 32

3-35
STEERING HEAD INSPECTION AND ADJUSTMENT
INSP
ADJ
2. Inspect:
9Bearing free play
Exist play Replace.
EC36U070
STEERING HEAD INSPECTION AND
ADJUSTMENT
1. Elevate the front wheel by placing a suitable
stand under the engine.
2. Check:
9Steering shaft
Grasp the bottom of the forks and gently
rock the fork assembly back and forth.
Free play Adjust steering head.
3. Check:
9Steering smooth action
Turn the handlebar lock to lock.
Unsmooth action Adjust steering ring
nut.
4. Adjust:
9Steering ring nut
Steering ring nut adjustment steps:
9Remove the number plate.
9Remove the handlebar and handle crown.
9Loosen the ring nut 1using the ring nut
wrench 2.
9Tighten the ring nut 3using ring nut wrench
4.
NOTE:
9Apply the lithium soap base grease on the
thread of the steering shaft.
9Set the torque wrench to the ring nut wrench
so that they form a right angle.
Ring nut wrench:
YU-33975/90890-01403
5XF-9-30-3B 5/6/03 6:32 PM Page 34

4-42
KICK AXLE, SHIFT SHAFT AND PRIMARY DRIVE GEARENG
EC4C3000
REMOVAL POINTSEC483111
Primary drive gear
1. Loosen:
9Bolt (primary drive gear) 1
NOTE:
Place an aluminum plate abetween the teeth of
the primary drive gear 2and driven gear 3.
EC4B3101
Kick axle assembly
1. Remove:
9Kick axle assembly 1
NOTE:
Unhook the torsion spring 2from the hole ain
the crankcase.
EC4C3101
Shift guide and shift lever assembly
1. Remove:
9Bolt (shift guide)
9Shift guide 1
9Shift lever assembly 2
NOTE:
The shift lever assembly is disassembled at the
same time as the shift guide.
EC4C4000
INSPECTION
EC4C4200
Kick axle and ratchet wheel
1. Check:
9Ratchet wheel 1smooth movement
Unsmooth movement
Replace.
9Kick axle 2
Wear/Damage
Replace.
9Spring 3
Broken
Replace.
5XF-9-30-4B 4/22/03 9:00 AM Page 30

4-43
KICK AXLE, SHIFT SHAFT AND PRIMARY DRIVE GEARENG
EC4B4400
Shift shaft
1. Inspect:
9Shift shaft 1
Bend/Damage
Replace.
9Spring 2
Broken
Replace.
EC484300
Primary drive gear and primary driven gear
1. Inspect:
9Primary drive gear 1
9Primary driven gear 2
Wear/Damage
Replace.
EC4C4400
Stopper lever
1. Inspect:
9Stopper lever 1
Wear/Damage
Replace.
9Bearing 2
Rotate outer race with a finger.
Rough spot/Seizure
Replace the stopper
lever.
9Tension spring 3
Broken
Replace.
EC4C4100
Shift guide and shift lever assembly
1. Inspect:
9Shift guide 1
9Shift lever 2
9Pawl 3
9Pawl pin 4
9Spring 5
Wear/Damage
Replace.
EC4C4300
Kick gear, kick idle gear and ratchet wheel
1. Inspect:
9Kick gear 1
9Kick idle gear 2
9Ratchet wheel 3
9Gear teeth a
9Ratchet teeth b
Wear/Damage
Replace.
5XF-9-30-4B 4/22/03 9:00 AM Page 32