Yamaha MBK X-MAX 300 2017 Service Manual page 223

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
New
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.
a. Remove the valve guide with the valve
guide remover "1".
VALVES AND VALVE SPRINGS
b. Install the new valve guide with the valve
guide installer "2" and valve guide remov-
er "1".
Valve guide position
11.98–12.02 mm (0.471–0.473 in)
a. Valve guide position
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.
TIP
After replacing the valve guide, reface the valve
seat.
Valve guide remover (ø5)
90890-04097
Valve guide remover (5.0 mm)
YM-04097
Valve guide installer (ø5)
90890-04098
Valve guide installer (5.0 mm)
YM-04098
Valve guide reamer (ø5)
90890-04099
Valve guide reamer (5.0 mm)
YM-04099
3. Eliminate:
• Carbon deposits
(from the valve face and valve seat)
5-28
3