Yamaha YZFR1W 2007 Service Manual page 224

• Valve-stem-to-valve-guide clearance
Out of specification → Replace the valve
guide.
• Valve-stem-to-valve-guide clearance =
Valve guide inside diameter "a" -
Valve stem diameter "b"
Valve-stem-to-valve-guide
ance
Valve-stem-to-valve-guide clear-
ance (intake)
0.010–0.037
0.0015 in)
Limit
0.080 mm (0.0032 in)
Valve-stem-to-valve-guide clear-
ance (exhaust)
0.025–0.052
0.0020 in)
Limit
0.100 mm (0.0039 in)
2. Replace:
• Valve guide
NOTE:
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.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the valve guide with the valve
guide remover "1".
VALVES AND VALVE SPRINGS
clear-
mm (0.0004–
mm (0.0010–
5-24
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 obtain the proper valve-stem-to-valve-
guide clearance.
NOTE:
After replacing the valve guide, reface the
valve seat.