Yamaha FJR13AG, Service Manual

Page: 355 / 784

VALVES AND VALVE SPRINGS
5-26
1. Measure:
• Valve-stem-to-valve-guide clearance
Out of specification
→
Replace the valve
guide.
2. Replace:
• Valve guide
TIP
To ease valve guide removal and installation,
and to maintain the correct fit, heat the cylinder
head to 100 °C (212 °F) in an oven.
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a. Remove the valve guide with the valve guide
remover “1”.
b. Install the new valve guide with the valve
guide installer “2” and valve guide remover
“1”.
c. After installing the valve guide, bore the valve
guide with the valve guide reamer “3” to ob-
tain the proper valve-stem-to-valve-guide
clearance.
TIP
After replacing the valve guide, reface the valve
seat.
• Valve-stem-to-valve-guide clearance =
Valve guide inside diameter “a” -
Valve stem diameter “b”
Valve-stem-to-valve-guide clear-
ance (intake)
0.010–0.037 mm (0.0004–0.0015
in)
Limit
0.080 mm (0.0032 in)
Valve-stem-to-valve-guide clear-
ance (exhaust)
0.020–0.047 mm (0.0008–0.0019
in)
Limit
0.100 mm (0.0039 in)