Yamaha WR450F, 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
30.100 ~ 30.200 mm
(1.1850 ~ 1.1890 in)
<Limit>: 30.000 mm
(1.1811 in)
b
22.450 ~ 22.550 mm
(0.8839 ~ 0.8878 in)
<Limit>: 22.350 mm
(0.8799 in)
Exhaust:
a
30.200 ~ 30.300 mm
(1.1890 ~ 1.1929 in)
<Limit>: 30.100 mm
(1.1850 in)
b
22.450 ~ 22.550 mm
(0.8839 ~ 0.8878 in)
<Limit>: 22.350 mm
(0.8799 in)
3. Measure:
• Runout (camshaft)
Out of specification
→
Replace.
Runout (camshaft):
Less than 0.03 mm (0.0012 in)