Yamaha YZ125N1 Service Manual page 152

CRANKCASE AND CRANKSHAFT
4-65
2. Inspect:
9Bearings 1
Rotate inner race with a finger.
Rough spot/Seizure
3. Inspect:
9Oil seal 1
Damage Replace.
EC4N4202
Crankshaft
1. Measure:
9Runout limit a
9Small end free play limit b
9Connecting rod big end side clearance c
9Crank width d
Out of specification
Use the dial gauge and a thickness gauge.
Dial gauge:
YU-3097/90890-01252
Standard
Runout 0.03 mm
limit: (0.0012 in)
Small end 0.8~1.0 mm
free play: (0.031~0.039 in)
Side 0.20~0.70 mm
clearance: (0.008~0.028in)
Crank 55.90~55.95 mm
width: (2.201~2.203 in)
EC4N5000
ASSEMBLY AND INSTALLATION
EC4N5300
Crankshaft bearing
1. Install:
9Bearing 1
To crankcase (left and right).
NOTE:
Install the bearing by pressing its outer race
parallel.
ENG
Replace.
Replace.
<Limit>
0.05 mm
(0.0020 in)
2.0 mm
(0.08 in)
—
—