Yamaha TT-R125LW, Owner'S Service Manual

Page: 322 / 468

4 - 69
ENG
CRANKCASE, CRANKSHAFT AND BALANCER
Crankcase
1. Inspect:
●
Contacting surface
a
Scratches
→
Replace.
●
Engine mounting boss
b
, crankcase
Cracks/damage
→
Replace.
2. Inspect:
●
Bearing
Rotate inner race with a finger.
Rough spot/seizure
→
Replace.
Crankshaft
1. Measure:
●
Runout limit
a
●
Connecting rod big end side clearance
b
●
Crank width
c
Out of specification
→
Replace.
Use the dial gauge and a thickness
gauge.
Dial gauge and stand:
YU-03097/90890-01252
Standard <Limit>
Runout
limit:
—
0.03 mm
(0.0012 in)
Side clear-
ance: 0.15 ~ 0.45 mm
(0.0059 ~ 0.0177 in)
0.50 mm
(0.02 in)
Crack
width: 46.95 ~ 47.00 mm
(1.848 ~ 1.850 in)
—