Yamaha LIT-11616-16-02 Model Vehicle User Manual


 
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ENG
CAMSHAFT, ROCKER ARMS AND VALVES
3.Check:
Valve face
Pitting/wear Grind the face.
Valve stem end
Mushroom shape or diameter larger than the
body of the stem Replace.
4.Measure:
Margin thickness a
Out of specification Replace.
Margin thickness:
Intake:
1.0 ~ 1.4 mm (0.0394 ~ 0.0551 in)
Exhaust:
0.8 ~ 1.2 mm (0.0315 ~ 0.0472 in)
5.Measure:
Runout (valve stem)
Out of specification Replace.
N
OTE:
When installing a new valve, always replace
the guide.
When a valve is removed or replaced,
always replace the oil seal.
6.Eliminate:
Carbon deposits
(from the valve face and valve seat)
7.Check:
Valve seat
Pitting/wear Reface the valve seat.
8.Measure:
Valve seat width a
Out of specification Reface the valve seat.
Runout limit:
0.01 mm (0.0004 in)
Valve seat width:
Intake:
1.2 ~ 1.4 mm (0.0472 ~ 0.0551 in)
<Limit>: 1.6 mm (0.0630 in)
Exhaust:
1.2 ~ 1.4 mm (0.0472 ~ 0.0551 in)
<Limit>: 1.6 mm (0.0630 in)