Yamaha XVS6501997 Service Manual page 117

CYLINDER HEADS
3. Measure:
S Cylinder head warpage
Out of specification ! Resurface.
Cylinder head warpage:
Less than 0.03 mm
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Warpage measurement and resurfacement
steps:
D Place a straightedge 1 and a feeler gauge
2 across the cylinder head.
D Use a feeler gauge to measure the warpage.
D If the warpage is out of specification, resur-
face the cylinder head.
D Place a 400 X 600 grit wet sandpaper on the
surface plate, and resurface the head using a
figure-eight sanding pattern.
NOTE:
To ensure an even surface rotate the cylinder
head several times.
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4. Inspect:
S Camshaft sprockets
Wear/damage ! Replace the camshaft
sprockets and the timing chain as a set.
a 1 / 4 tooth
b Correct
1 Roller
2 Sprocket
5. Check:
S One-way cam operation (tensioner)
Unsmooth operation ! Replace.
4-13
ENG