Yamaha WR250FM Bicycle User Manual


 
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ENG
CRANKCASE AND CRANKSHAFT
Crankshaft
1. Remove:
Crankshaft 1
Use the crankcase separating tool 2.
CAUTION:
Do not use a hammer to drive out the
crankshaft.
Crankcase bearing
1. Remove:
Bearing 1
N
OTE:
Remove the bearing from the crankcase by
pressing its inner race.
Do not use the removed bearing.
Crankcase separating tool:
YU-1135-A/90890-01135
INSPECTION
Timing chain and timing chain guide
1. Inspect:
Timing chain
Cracks/stiff Replace the timing chain
and camshaft sprocket as a set.
2. Inspect:
Timing chain guide
Wear/damage Replace.
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.
3. Inspect:
Oil seal
Damage Replace.