2006 YAMAHA YZ250LC wheel

4-57
CDI MAGNETOENG
EC4L5000
ASSEMBLY AND INSTALLATION
EC4L5172
CDI magneto
1. Install:
9Stator 1
9Screw (stator) 2
NOTE:
Temporarily tighten the screw (stator) at this
point.
2. Remove:
9Rotor 1
Use the flywheel puller 2.
NOTE:
When installing the flywheel puller, turn it coun-
terclockwise.
EC4L3000
REMOVAL POINTS
EC4L3102
Rotor
1. Remove:
9Nut (rotor) 1
9Plain washer 2
Use the rotor holding tool 3.
EC4L4000
INSPECTION
EC4L4101
CDI magneto
1. Inspect:
9Rotor inner surface a
9Stator outer surface b
Damage
Inspect the crankshaft runout
and crankshaft bearing.
If necessary, replace CDI magneto and/or
stator.
EC4L4200
Woodruff key
1. Inspect:
9Woodruff key 1
Damage
Replace.
Rotor holding tool:
YU-1235/90890-01235
Flywheel puller:
YM-1189/90890-01189
1P8-9-31-4C 5/12/05 1:20 PM Page 16

4-75
TRANSMISSION, SHIFT CAM AND SHIFT FORKENG
4. Install:
9Spacer 1
NOTE:
9Apply the lithium soap base grease on the oil
seal lip.
9When installing the spacer into the crankcase,
pay careful attention to the crankcase oil seal
lip.
9Install the spacer with its chamfered side a
facing the crankcase.
3. Install:
9Plain washer 1
9Circlip 2
NOTE:
9Be sure the circlip sharp-edged corner ais
positioned opposite side to the plain washer
and gear b.
9Be sure the circlip end cis positioned at axle
spline groove d.
2. Install:
92nd wheel gear (23 T) 1
94th wheel gear (24 T) 2
93rd wheel gear (23 T) 3
95th wheel gear (20 T) 4
91st wheel gear (27 T) 5
9O-ring 6
To drive axle 7.
NOTE:
9Apply the molybdenum disulfide oil on the inner
and end surface of the idler gear and on the
inner surface of the sliding gear, then install.
9Apply the lithium soap base grease on the O-
ring.
1P8-9-31-4C 5/12/05 1:21 PM Page 52

4-76
TRANSMISSION, SHIFT CAM AND SHIFT FORKENG
5. Install:
9Shift fork 1 (L) 1
9Shift fork 2 (C10) 2
9Shift fork 3 (R) 3
9Shift cam 4
To main axle and drive axle.
NOTE:
9Apply the molybdenum disulfide oil on the shift
fork grooves.
9Mesh the shift fork #1 (L) with the 4th wheel
gear 5and #3 (R) with the 5th wheel gear 7
on the drive axle.
9Mesh the shift fork #2 (C10) with the 3rd pinion
gear 6on the main axle.
6. Install:
9Transmission assembly 1
To crankcase (left) 2.
NOTE:
Apply the transmission oil on the bearings and
guide bars.
7. Check:
9Shifter operation
9Transmission operation
Unsmooth operation
Repair.
1P8-9-31-4C 5/12/05 1:21 PM Page 54

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 Bolt (axle holder) 4 Only loosening.
2 Nut (front wheel axle) 1
3 Front wheel axle 1
4 Front wheel 1
5 Collar 2
6 Oil seal 2
7 Bearing 2 Refer to “REMOVAL POINTS”.
8 Brake disc 1
EC500000
CHASSISEC590000
FRONT WHEEL AND REAR WHEELEC598000
FRONT WHEEL
2
13
3
Extent of removal:1Front wheel removal2Wheel bearing removal3Brake disc removal
w
Support the machine securely so there is no dan-
ger of it falling over.
23 Nm (2.3 m•kg, 17 ft•lb)
23 Nm (2.3 m•kg, 17 ft•lb)
105 Nm (10.5 m•kg, 75 ft•lb)
12 Nm (1.2 m•kg, 8.7 ft•lb)
1C3-9-31-5A 4/22/05 1:13 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 disc 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)
16 Nm (1.6 m•kg, 11 ft•lb)
16 Nm (1.6 m•kg, 11 ft•lb)
42 Nm (4.2 m•kg, 30 ft•lb)
1C3-9-31-5A 4/22/05 1:13 PM Page 4

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 limitRepair/Replace.
2. Inspect:
9Bearing
Rotate inner race with a finger.
Rough spot/SeizureReplace.
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)
1C3-9-31-5A 4/22/05 1:13 PM Page 6

5-4
CHASFRONT WHEEL AND REAR WHEEL
EC514200
Wheel axle
1. Measure:
9Wheel axle 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 axle.
EC594200
Brake disc
1. Measure:
9Brake disc deflection (only rear brake disc)
Use the dial gauge 1.
Out of specificationInspect wheel runout.
If wheel runout is in good condition, re-
place the brake disc.
2. Measure:
9Brake disc thickness a
Out of limitReplace.
Wheel axle bending limit:
0.5 mm (0.020 in)
Disc wear limit:
Standard
Front 3.0 mm (0.12 in) 2.5 mm (0.10 in)
Rear 4.0 mm (0.16 in) 3.5 mm (0.14 in)
Disc deflection limit:
Standard
Rear —
0.15 mm (0.006 in)
1C3-9-31-5A 4/22/05 1:13 PM Page 8

5-5
CHASFRONT WHEEL AND REAR WHEEL
EC595000
ASSEMBLY AND INSTALLATION
EC595101
Front wheel
1. Install:
9Bearing (left) 1
9Spacer 2
9Bearing (right) 3
9Oil seal 4
NOTE:
9Apply the lithium soap base grease on the
bearing and oil seal lip when installing.
9Use a socket that matches the outside diam-
eter of the race of the bearing.
9Left side of bearing shall be installed first.
9Install the oil seal with its manufacture’s
marks or numbers facing outward.
cC
Do not strike the inner race of the bearing.
Contact should be made only with the out-
er race.
2. Install:
9Brake disc 1
9Bolt (brake disc) 2
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
3. Install:
9Collar 1
NOTE:
9Apply the lithium soap base grease on the oil
seal lip.
9Install the collars with their projections afacing
the wheel.
4. Install:
9Wheel
NOTE:
Install the brake disc 1between the brake pads
2correctly.
12 Nm (1.2 m•kg, 8.7 ft•lb)
1C3-9-31-5A 4/22/05 1:13 PM Page 10