2003 YAMAHA YZ125LC clutch

4-30
ENGCLUTCH AND PRIMARY DRIVEN GEAR
Extent of removal Order Part name Q’ty Remarks
CLUTCH PLATE AND
FRICTION PLATE REMOVAL
Preparation for Drain the transmission oil.
Refer to “TRANSMISSION OIL REPLACE-
removalMENT“ section in the CHAPTER 3.
Bolt (brake pedal) Shift the brake pedal downward.
Clutch cable Disconnect at engine side.
1 Clutch cover 1
2 Screw (clutch spring) 5
3 Clutch spring 5
4 Pressure plate 1
5 Push rod 1
6 Plain washer 2
7 Bearing 1
8 Friction plate 8
9 Clutch plate 7
Extent of removal:1Clutch plate and friction plate removal
EC490000
CLUTCH AND PRIMARY DRIVEN GEAREC498000
CLUTCH PLATE AND FRICTION PLATE
1
10 Nm (1.0 m•kg, 7.2 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)

4-31
ENGCLUTCH AND PRIMARY DRIVEN GEAR
EC498100
PRIMARY DRIVEN GEAR
Extent of removal Order Part name Q’ty Remarks
PRIMARY DRIVEN GEAR
REMOVAL
1 Nut (clutch boss) 1
Use special tool.
2 Lock washer 1
Refer to “REMOVAL POINTS”.
3 Clutch boss 1
4
Plain washer [φ34 mm (1.34 in)] 1
5 Primary driven gear 1
6 Bearing 1
7
Plain washer [φ34 mm (1.34 in)]1
8 Push lever 1
Extent of removal:1Primary driven gear removal2Push lever removal
1
2





80 Nm (8.0 m•kg, 58 ft•lb)
7 Nm (0.7 m•kg, 5.1 ft•lb)
5UN-9-30-4B 1/7/04 4:36 PM Page 28

4-32
ENGCLUTCH AND PRIMARY DRIVEN GEAR
EC493000
REMOVAL POINTS
EC483211
Clutch boss
1. Remove:
9Nut 1
9Lock washer 2
9Clutch boss 3
NOTE:
Straighten the lock washer tab and use the
clutch holding tool 4, 5to hold the clutch boss.
å
For USA and CDN
∫
Except for USA and CDN
EC494000
INSPECTION
EC484100
Clutch housing and boss
1. Inspect:
9Clutch housing 1
Cracks/Wear/Damage  Replace.
9Clutch boss 2
Scoring/Wear/Damage Replace.
EC484201
Primary driven gear
1. Check:
9Circumferential play
Free play exists Replace.
9Gear teeth a
Wear/ Damage Replace.
EC484400
Clutch spring
1. Measure:
9Clutch spring free length a
Out of specification Replace springs as
a set.
Clutch holding tool:
YM-91042................................
4 4
90890-04086............................5 5
Clutch spring free length:
Standard
41.2 mm 39.2 mm
(1.622 in) (1.543 in)
å
∫å

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ENGCLUTCH AND PRIMARY DRIVEN GEAR
EC484500
Friction plate
1. Measure:
9Friction plate thickness
Out of specification Replace friction
plate as a set.
Measure at all four points.
EC484600
Clutch plate
1. Measure:
9Clutch plate warpage
Out of specification Replace clutch plate
as a set.
Use a surface plate 1and thickness
gauge 2.
EC494100
Push lever and push rod
1. Inspect:
9Push lever 1
9Push rod 2
Wear/Damage Replace.
EC494200
Clutch cover
1. Inspect:
9Push rod bearing portion a
Wear/Damage Replace.
Friction plate thickness:
Standard
2.9~3.1 mm 2.8 mm
(0.114~0.122 in) (0.110 in)
Warp limit:
0.2 mm (0.008 in)

4-34
ENGCLUTCH AND PRIMARY DRIVEN GEAR
EC495000
ASSEMBLY AND INSTALLATION
EC495240
Clutch
1. Install:
9Plain washer [
φ34 mm (1.34 in)] 1
9Spacer 2
9Bearing 3
9Primary driven gear 4
NOTE:
Apply the transmission oil on the spacer, bearing
and primary driven gear inner circumference.
2. Install:
9Plain washer [
φ34 mm (1.34 in)] 1
9Clutch boss 2
3. Install:
9Lock washer 1
9Nut (clutch boss) 2
NOTE:
Use the clutch holding tool 3, 4to hold the
clutch boss.
å
For USA and CDN
∫
Except for USA and CDN
4. Bend the lock washer 1tab.
80 Nm (8.0 m•kg, 58 ft•lb)
Clutch holding tool:
YM-91042...............................3 3
90890-04086...........................4 4
å
∫
5UN-9-30-4B 1/7/04 4:36 PM Page 34

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ENGCLUTCH AND PRIMARY DRIVEN GEAR
5. Install:
9Friction plate 1 1
9Clutch plate 2
9Friction plate 2 3
NOTE:
9Install the clutch plates and friction plates alter-
nately on the clutch boss, starting with a friction
plate and ending with a friction plate.
9Use the friction plates 1 for the first and final
while paying attention to the difference in sur-
face pattern.
9Apply the transmission oil on the friction plates
and clutch plates.
10 Nm (1.0 m•kg, 7.2 ft•lb)
8. Install:
9Clutch spring 1
9Screw (clutch spring) 2
NOTE:
Tighten the screws in stage, using a crisscross
pattern.
6. Install:
9Push rod 1
9Plain washer 2
9Bearing 3
To pressure plate 4.
NOTE:
Apply the lithium soap base grease on the bear-
ing, plain washer and push rod.
7. Install:
9Pressure plate 1

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ENGCLUTCH AND PRIMARY DRIVEN GEAR
EC495122
Push lever
1. Install:
9Torsion spring 1
9Push lever 2
To push lever axle 3.
NOTE:
Temporarily install the torsion spring and push
lever at this point.
2. Check:
9Push lever position
NOTE:
When pushing the push lever forward, alignment
mark bshould be positioned between area a.
If not, reinstall the push lever.
3. Adjust:
9Push lever position 10. Install:
9Clutch cover 1
9Bolt (clutch cover) 2
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
10 Nm (1.0 m•kg, 7.2 ft•lb)
Adjustment steps:
9Remove the push lever 1from the push
lever axle 2.
9Re-install the push lever so that the projec-
tion is positioned between alignment marks
when pushing the push lever forward.
9. Install:
9Gasket (clutch cover) 1
NOTE:
Position the rack aon the push rod backward.

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ENGCLUTCH AND PRIMARY DRIVEN GEAR
4. Install:
9Plain washer 1
9Circlip 2