Yamaha TT-R125(R) Owner's Service Manual page 346

CRANKCASE, CRANKSHAFT AND BALANCER
Crankcase
1. Inspect:
Contacting surface a
G
Scratches → Replace.
Engine mounting boss b, crankcase
G
Cracks/damage → Replace.
2. Inspect:
Bearing
G
Rotate inner race with a finger.
Rough spot/seizure → Replace.
Crankshaft
1. Measure:
Runout limit a
G
Connecting rod big end side clearance
G
b
Crank width c
G
Out of specification → Replace.
Use the dial gauge and a thickness
gauge.
Dial gauge & stand set:
YU-3097/90890-01252
Runout
limit:
Side clear- 0.15 ~ 0.45 mm
ance: (0.0059 ~ 0.0177 in)
Crack 46.95 ~ 47.00 mm
width: (1.848 ~ 1.850 in)
4 - 69
ENG
Standard <Limit>
0.03 mm
—
(0.0012 in)
0.50 mm
(0.02 in)
—