2001 YAMAHA YZ125LC oil

4-66
ENGCRANKCASE AND CRANKSHAFT
EC4N5102
Oil seal
1. Install:
9Oil seal (left) 1
9Oil seal (right) 2
NOTE:
9Apply the lithium soap base grease on the oil
seal lip.
9Install the oil seal with its manufacture’s marks
or numbers facing outward.
EC4N5272
Crankshaft
1. Install:
9Crankshaft 1
Use the crankshaft installing tool 2, 3, 4
ŒFor USA and CDN
ºExcept for USA and CDN
NOTE:
9Hold the connecting rod at top dead center with
one hand while turning the nut of the installing
tool with the other. Operate the installing tool
until the crankshaft bottoms against the bear-
ing.
9Before installing the crankshaft, clean the con-
tacting surface of crankcase.
9Apply the lithium soap base grease on the oil
seal lip.
cC
Do not use a hammer to drive in the crank-
shaft.
Crankshaft installing tool:
Pot 2 2
:
YU-90050/90890-01274
Bolt 3 3
:YU-90050/90890-01275
Adapter 4 4
:YM-1277/90890-01277
μ
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4-68
ENGCRANKCASE AND CRANKSHAFT
6. Install:
9Holder 1
9Bolt (holder) 2
7. Install:
9Segment 1
9Bolt (segment) 2
NOTE:
9When installing the segment onto the shift cam
3, align the punch mark awith the dowel pin
b.
9Turn the segment clockwise until it stops and
tighten the bolt.
8. Remove:
9Sealant
Forced out on the cylinder mating surface.
9. Apply:
9Engine oil
To the crank pin, bearing, oil delivery hole
and connecting rod big end washer.
10. Check:
9Crankshaft and transmission operation
Unsmooth operation ÕRepair.
30 Nm (3.0 m•kg, 22 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)
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4-71
ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
EC4H4801
Shift fork, shift cam and segment
1. Inspect:
9Shift fork 1
Wear/Damage/Scratches ÕReplace.
2. Inspect:
9Shift cam 1
9Segment 2
9Guide bar 3
Bend/Wear/Damage ÕReplace.
3. Check:
9Shift fork movement
On its guide bar.
Unsmooth operation ÕReplace shift fork
and/or guide bar.
NOTE:
For a malfunctioning shift fork, replace not only
the shift fork itself but the two gears each adja-
cent to the shift fork.
EC4H5000
ASSEMBLY AND INSTALLATION
EC4H5202
Transmission
1. Install:
95th pinion gear (23T) 1
93rd/4th pinion gear (17T/21T) 2
96th pinion gear (24T) 3
92nd pinion gear (15T) 4
To main axle 5.
NOTE:
9Apply the molybdenum disulfide oil on the 5th
and 6th pinion gears inner circumference.
9Apply the transmission oil on the 2nd and
3rd/4th pinion gears inner circumference.
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4-72
ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
2. Install:
92nd wheel gear (28T) 1
96th wheel gear (24T) 2
94th wheel gear (27T) 3
93rd wheel gear (26T) 4
95th wheel gear (26T) 5
91st wheel gear (30T) 6
To drive axle 7.
NOTE:
9Apply the molybdenum disulfide oil on the 1st,
2nd, 3rd and 4th wheel gears inner circumfer-
ence.
9Apply the transmission oil on the 5th and 6th
wheel gears inner circumference.
3. Install:
9Plain washer 1
9Circlip 2
NOTE:
9Be sure the circlip sharp-edged corner ais po-
sitioned opposite side to the plain washer and
gear b.
9Be sure the circlip end cis positioned at axle
spline groove d.
4. Install:
9Main axle 1
9Drive axle 2
NOTE:
9Apply the lithium soap base grease on the
crankcase oil seal lip.
9When installing the drive axle into the
crankcase, pay careful attention to the
crankcase oil seal lip.
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4-73
ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
EC4H5331
Shift cam and shift fork
1. Install:
9Shift fork 1 (L) 1
9Shift fork 2 2
9Shift fork 3 (R) 3
NOTE:
9Mesh the shift fork #1 (L) with the 6th wheel
gear 4and #3 (R) with the 5th wheel gear 6
on the drive axle.
9Mesh the shift fork #2 with the 3rd/4th pinion
gear 5on the main axle.
2. Install:
9Shift cam 1
NOTE:
Apply the transmission oil on the shift cam.
3. Install:
9Guide bar (short) 1
9Guide bar (long) 2
NOTE:
9Apply the transmission oil on the guide bars.
9Be sure the long bar is inserted into the shift
forks #1 and #3 and the short one into #2.
4. Check:
9Shifter operation
9Transmission operation
Unsmooth operation ÕRepair.
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5-1
CHASFRONT WHEEL AND REAR WHEEL
Extent of removal Order Part name Q’ty Remarks
FRONT WHEEL REMOVAL
Preparation for
Hold the machine by placing the
removalsuitable stand under the engine.
1 Hose cover 1
2 Bolt (brake hose holder) 2 Only loosening.
3 Bolt (axle holder) 4 Only loosening.
4 Nut (front wheel axle) 1
5 Front wheel axle 1
6 Front wheel 1
7 Collar 2
8 Oil seal 2
9 Bearing 2 Refer to “REMOVAL POINTS”.
10 Brake disk 1
EC500000
CHASSISEC590000
FRONT WHEEL AND REAR WHEELEC598000
FRONT WHEEL
2
13
3
Extent of removal:1Front wheel removal2Wheel bearing removal3Break disc removal
w
Support the machine securely so there is no dan-
ger of it falling over.
5
23 Nm (2.3 m•kg, 17 ft•lb)
23 Nm (2.3 m•kg, 17 ft•lb)
10 Nm (1.0 m•kg, 7.2 ft•lb)
105 Nm (10.5 m•kg, 75 ft•lb)
16 Nm (1.6 m•kg, 11 ft•lb)
7 Nm (0.7 m•kg, 5.1 ft•lb)
12 Nm (1.2 m•kg, 8.7 ft•lb)
5MV-9-30-5A 6/19/00 1:35 PM Page 2

5-2
CHASFRONT WHEEL AND REAR WHEEL
EC598100
REAR WHEEL
Extent of removal:1Rear wheel removal2Wheel bearing removal3Brake disc removal
Extent of removal Order Part name Q’ty Remarks
REAR WHEEL REMOVAL
Preparation for
Hold the machine by placing the
removalsuitable stand under the engine.
1 Nut (rear wheel axle) 1
2 Rear wheel axle 1
3 Chain puller 2
4 Rear wheel 1 Refer to “REMOVAL POINTS”.
5 Collar 2
6 Driven sprocket 1
7 Oil seal 2
8 Circlip 1
9 Bearing 2 Refer to “REMOVAL POINTS”.
10 Brake disk 1
2
13
3
w
Support the machine securely so there is no dan-
ger of it falling over.
125 Nm (12.5 m•kg, 90 ft•lb)
14 Nm (1.4 m•kg, 10 ft•lb)
42 Nm (4.2 m•kg, 30 ft•lb)
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5-3
CHASFRONT WHEEL AND REAR WHEEL
EC593000
REMOVAL POINTS
EC523101
Rear wheel
1. Remove:
9Wheel 1
NOTE:
Push the wheel forward and remove the drive
chain 2.
EC513201
Wheel bearing (if necessary)
1. Remove:
9Bearing 1
NOTE:
Remove the bearing using a general bearing
puller 2.
EC594000
INSPECTION
EC514100
Wheel
1. Measure:
9Wheel runout
Out of limitÕRepair/Replace.
2. Inspect:
9Bearing
Rotate inner race with a finger.
Rough spot/SeizureÕReplace.
NOTE:
Replace the bearings, oil seal and wheel collar
as a set.
Wheel runout limit:
Radial 1 1
: 2.0mm (0.08 in)
Lateral 2 2
: 2.0mm (0.08 in)
5MV-9-30-5A 6/19/00 1:35 PM Page 6