2005 YAMAHA YZ125LC oil

5-31
CHASFRONT FORK
Base valve
1. Inspect:
9Base valve 1
Wear/DamageReplace.
ContaminationClean.
9O-ring 2
Wear/DamageReplace.
9Bush 3
Wear/DamageReplace base valve.
9Spring 4
Damage/FatigueReplace base valve.
9Air bleed screw 5
Wear/DamageReplace base valve.
EC554400
Fork spring
1. Measure:
9Fork spring free length a
Out of specificationReplace.
EC554502
Inner tube
1. Inspect:
9Inner tube surface a
Score marksRepair or replace.
Use #1,000 grit wet sandpaper.
Damaged oil lock pieceReplace.
9Inner tube bends
Out of specificationReplace.
Use the dial gauge 1.
NOTE:
The bending value is shown by one half of the
dial gauge reading.
w
Do not attempt to straighten a bent inner
tube as this may dangerously weaken the
tube.
Standard
465 mm 460 mm
(18.3 in) (18.1 in)Fork spring free length:
Inner tube bending limit:
0.2 mm (0.008 in)
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CHASFRONT FORK
EC554600
Outer tube
1. Inspect:
9Outer tube 1
Score marks/Wear/DamageReplace.
Adjuster
1. Inspect:
9Adjuster 1
9O-ring 2
Wear/DamageReplace.
EC555000
ASSEMBLY AND INSTALLATIONEC5551D0
Front fork assembly
1. Wash the all parts in a clean solvent.
2. Stretch the damper assembly fully.
3. Fill:
9Front fork oil 1
To damper assembly.
cC
9Be sure to use recommended fork oil. If
other oils are used, they may have an ex-
cessively adverse effect on the front fork
performance.
9Never allow foreign materials to enter the
front fork.
Recommended oil:
Suspension oil “S1”
Oil capacity:
195cm
3(6.86 Imp oz, 6.59 US oz)
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CHASFRONT FORK
4. After filling, pump the damper assembly 1
slowly up and down (about 200 mm (7.9 in)
stroke) several times to bleed the damper
assembly of air.
NOTE:
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, repeat the steps 2 to
4.
5. Inspect:
9Oil amount
While keeping the damper assembly fully
stretched, check that the oil is above the
step aon the damper assembly.
Below the stepReplenish fork oil above
the step.
6. Tighten:
9Locknut 1
NOTE:
Fully finger tighten the locknut onto the
damper assembly.
7. Loosen:
9Compression damping adjuster 1
NOTE:
9Loosen the compression damping adjuster fin-
ger tight.
9Record the set position of the adjuster (the
amount of turning out the fully turned in posi-
tion).
8. Install:
9Base valve 1
To damper assembly 2.
NOTE:
First bring the damper rod pressure to a maxi-
mum. Then install the base valve while releas-
ing the damper rod pressure.
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9. Tighten:
9Base valve 1
NOTE:
Hold the damper assembly with the cap bolt
ring wrench
2and use the cap bolt wrench 3
to tighten the base valve with specified torque.
10. After filling, pump the damper assembly 1
slowly up and down more than 10 times to
distribute the fork oil.
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CHASFRONT FORK
11. While protecting the damper assembly 1
with a rag and compressing fully, allow
excessive oil to overflow on the base valve
side.
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Take care not to damage the damper
assembly.
12. Allow the overflowing oil to escape at the
hole ain the damper assembly.
13. Check:
9Damper assembly smooth movement
Tightness/Binding/Rough spots  Repeat
the steps 2 to 12.
29 Nm (2.9 m•kg, 21 ft•lb)
Cap bolt wrench:
YM-01500/90890-01500
Cap bolt ring wrench:
YM-01501/90890-01501
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5-35
CHASFRONT FORK
14. Install:
9Dust seal 1
9Stopper ring 2
9Oil seal 3
9Oil seal washer 4
9Slide metal 5
To inner tube 6.
NOTE:
9Apply the fork oil on the inner tube.
9When installing the oil seal, use vinyl seat a
with fork oil applied to protect the oil seal lip.
9Install the oil seal with its manufacture's marks
or number facing the axle holder side.
9Install the oil seal washer with its projections b
facing upward.
15. Install:
9Piston metal 1
NOTE:
Install the piston metal onto the slot on inner
tube.
16. Install:
9Outer tube 1
To inner tube 2.
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CHASFRONT FORK
17. Install:
9Slide metal 1
9Oil seal washer 2
To outer tube slot.
NOTE:
Press the slide metal into the outer tube with
fork seal driver 3.
18. Install:
9Oil seal 1
NOTE:
Press the oil seal into the outer tube with fork
seal driver 2.
19. Install:
9Stopper ring 1
NOTE:
Fit the stopper ring correctly in the groove in the
outer tube.
20. Install:
9Dust seal 1
NOTE:
Apply the lithium soap base grease on the inner
tube.
Fork seal driver:
YM-01442/90890-01442
Fork seal driver:
YM-01442/90890-01442
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5-38
CHASFRONT FORK
26. Install:
9Push rod 1
9Copper washer 2
9Adjuster 3
To damper assembly 4.
NOTE:
9While compressing the inner tube 5, set the
cap bolt ring wrench 7between the inner tube
and locknut 6.
9Fully finger tighten the adjuster onto the
damper assembly.
27. Inspect:
9Gap abetween adjuster 1and locknut 2.
Out of specificationRetighten and read-
just the locknut.
NOTE:
If the adjuster is installed out of specification,
proper damping force cannot be obtained.
28. Tighten:
9Adjuster (locknut) 1
NOTE:
Hold the locknut 2and tighten the adjuster with
specified torque.
29. Install:
9Adjuster 1
To inner tube.
30. Fill:
9Front fork oil 1
From outer tube top.
*For EUROPE
29 Nm (2.9 m•kg, 21 ft•lb)
55 Nm (5.5 m•kg, 40 ft•lb)
Gap a abetween adjuster and locknut
0.5~1.0mm (0.02~0.04 in)
Recommended oil:
Suspension oil "S1"
Standard oil amount:
245 cm
3(8.62 Imp oz, 8.28 US oz)
*250 cm
3(8.80 Imp oz, 8.45 US oz)
Extent of adjustment:
200
~300 cm3(7.04~10.6 Imp oz,
6.76~10.1 US oz)
Cap bolt ring wrench:
YM-01501/90890-01501
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CHASFRONT FORK
31. Install:
9Damper assembly 1
To outer tube.
NOTE:
Temporarily tighten the damper assembly.
32. Install:
9Protector guide 1
EC5552A1
Installation
1. Install:
9Front fork 1
NOTE:
9Temporarily tighten the pinch bolts (under
bracket).
9Do not tighten the pinch bolts (handle crown)
yet.
2. Tighten:
9Damper assembly 1
NOTE:
Use the cap bolt ring wrench 2to tighten the
damper assembly with specified torque.
w
Never fail to make the oil amount adjustment
between the maximum and minimum
amount and always adjust each front fork to
the same setting. Uneven adjustment can
cause poor handling and loss of stability.
cC
9Be sure to use recommended fork oil. If
other oils are used, they may have an ex-
cessively adverse effect on the front fork
performance.
9Never allow foreign materials to enter the
front fork.
30 Nm (3.0 m•kg, 22 ft•lb)
Cap bolt ring wrench:
YM-01501/90890-01501
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