Yamaha YZ250F(P)/LC, Руководство по эксплуатации для владельца

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ENG
VALVES AND VALVE SPRINGS
INSPECTION
Valve
1. Measure:
●
Stem-to-guide clearance
Out of specification
→
Replace the
valve guide.
Stem-to-guide clearance =
valve guide inside diameter
a
–
valve stem diameter
b
Clearance (stem to guide):
Intake:
0.010 ~ 0.037 mm
(0.0004 ~ 0.0015 in)
<Limit>: 0.08 mm (0.003 in)
Exhaust:
0.025 ~ 0.052 mm
(0.0010 ~ 0.0020 in)
<Limit>: 0.10 mm (0.004 in)
2. Replace:
●
Valve guide
Replacement steps:
NOTE:
To ease guide removal, installation and to
maintain correct fit heat the cylinder head in
an over to 100 ˚C (212 ˚F).
●
Remove the valve guide using a valve
guide remover
1 .
●
Install the new valve guide using a valve
guide remover
1 and valve guide installer
2
.
●
After installing the valve guide, bore the
valve guide using a valve guide reamer
3
to obtain proper stem-to-guide clearance.