Yamaha YZ450F(V), Owner'S Service Manual

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ENG
CAMSHAFTS
6. Remove:
• Clips
• Exhaust camshaft
1
• Intake camshaft
2
NOTE:
Attach a wire
3
to the timing chain to prevent
it from falling into the crankcase.
1
2
3
INSPECTION
Camshaft
1. Inspect:
• Cam lobes
Pitting/scratches/blue discoloration
→
Replace.
2. Measure:
• Cam lobes length
a
and
b
Out of specification
→
Replace.
Cam lobes length:
Intake:
a
31.200 ~ 31.300 mm
(1.2283 ~ 1.2323 in)
<Limit>: 31.100 mm
(1.2244 in)
b
22.550 ~ 22.650 mm
(0.8878 ~ 0.8917 in)
<Limit>: 22.450 mm
(0.8839 in)
Exhaust:
a
30.950 ~ 31.050 mm
(1.2185 ~ 1.2224 in)
<Limit>: 30.850 mm
(1.2146 in)
b
22.494 ~ 22.594 mm
(0.8856 ~ 0.8895 in)
<Limit>: 22.394 mm
(0.8817 in)
3. Measure:
• Runout (camshaft)
Out of specification
→
Replace.
Runout (camshaft):
Less than 0.03 mm (0.0012 in)