Yamaha RX10K Supplementary Service Manual page 292

VALVES AND VALVE SPRINGS
Replacement steps:
S Remove the valve guide with a valve guide
remover 1 .
S Install the new valve guide with a valve guide
installer 2 and valve guide remover 1 .
S After installing the valve guide, bore the
valve guide with a valve guide reamer 3 to
obtain the proper valve-stem-valve-guide
clearance.
NOTE:
After replacing the valve guide, reface the valve
seat.
3. Eliminate:
S Carbon deposits
(from the valve face and valve seat)
4. Inspect:
S Valve face
Pitting/wear ! Grind the valve face.
S Valve stem end
Mushroom shape or diameter larger than the
body of the valve stem ! Replace the valve.
5. Measure:
S Valve margin thickness a
Out of specification ! Replace the valve.
5-25
ENG
Valve guide remover:
Intake (ø4)
90890-04111, YM-04111
Exhaust (ø4.5)
90890-04116, YM-04116
Valve guide installer:
Intake (ø4)
90890-04112, YM-04112
Exhaust (ø4.5)
90890-04117, YM-04117
Valve guide reamer:
Intake
90890-04113, YM-04113
Exhaust
90890-04118, YM-04118
Valve margin thickness:
0.5 X 0.9 mm
(0.020 X 0.035 in)