Yamaha YZ450F(S), Owner'S Service Manual

Page: 288 / 642

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ENG
CAMSHAFTS
4. Measure:
●
Camshaft-to-cap clearance
Out of specification
→
Measure cam-
shaft journal diameter.
Camshaft-to-cap clearance:
0.020 ~ 0.054 mm
(0.0008 ~ 0.0021 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
camshaft.
Within specification
→
Replace cam-
shaft 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:
21.967 ~ 21.980 mm
(0.8648 ~ 0.8654 in)