Yamaha MX775 - Checking the Crankshaft

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ENGINE
PISTONS, CAMSHAFT, CRANKCASE, AND CRANKSHAFT
CHECKING THE CRANKSHAFT
1. Check:
• Crankshaft sprocket “1”
Damage/wear  Replace the crankshaft.
2. Measure:
• Crankshaft runout limit
Out of specification  Replace.
Use a dial indicator gauge.
3. Measure:
• Crank pin outside diameter “a”
Out of specification  Replace.
Use a micrometer.
Top ring
End gap (installed):
0.20–0.35 mm (0.0079–0.0138 in)
Limit:
0.60 mm (0.0236 in)
2nd ring
End gap (installed):
0.20–0.35 mm (0.0079–0.0138 in)
Limit:
0.60 mm (0.0236 in)
Oil ring
End gap (installed):
0.20–0.70 mm (0.0079–0.0276 in)
1
Dial indicator gauge:
YU-A8428
Runout limit:
0.03 mm (0.0012 in)
a
Crank pin outside diameter:
40.950–41.050 mm (1.6122–1.6161 in)