Yamaha XT250X 2008 Service Manual page 165

Valve-stem-to-valve-guide
ance
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)
0.025–0.052 mm (0.0010–0.0020
in)
Limit
0.100 mm (0.0039 in)
2. Replace:
Valve guide
G
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.
MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
a. Remove the valve guide with the valve guide
remover "1".
All manuals and user guides at all-guides.com
VALVES AND VALVE SPRINGS
clear-
5-19
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.
NOTE:
After replacing the valve guide, reface the valve
seat.