Yamaha WR450F, Owner'S Service Manual

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4 - 28
ENG
CAMSHAFTS
4. Measure:
• Camshaft-to-cap clearance
Out of specification
→
Measure camshaft
journal diameter.
Camshaft-to-cap clearance:
0.028 ~ 0.062 mm
(0.0011 ~ 0.0024 in)
<Limit>: 0.08 mm (0.003 in)
Measurement steps:
• Install the camshaft onto the cylinder
head.
• Position a strip of Plastigauge
®
1
onto the
camshaft.
• Install the circlip, dowel pins and camshaft
caps.
T
R
.
.
Bolt (camshaft cap):
10 Nm (1.0 m • kg, 7.2 ft • lb)
NOTE:
• Tighten the bolts (camshaft cap) in a criss-
cross pattern from innermost to outer
caps.
• Do not turn the camshaft when measuring
clearance with the Plastigauge
®
.
• Remove the camshaft caps and measure
the width of the Plastigauge
®
1
.
5. Measure:
• Camshaft journal diameter
a
Out of specification
→
Replace the cam-
shaft.
Within specification
→
Replace camshaft
case and camshaft caps as a set.
Camshaft sprocket
1. Inspect:
• Camshaft sprocket
1
Wear/damage
→
Replace the camshaft
assembly and timing chain as a set.
Camshaft journal diameter:
21.959 ~ 21.972 mm
(0.8645 ~ 0.8650 in)