Valves And Valve Guides - Yamaha ttr230 Service Manual

INSPECTION AND REPAIR
NOTE:
In order to achieve the best polishing
results, occasionally and lightly, beat the
valve face on the seat while turning the
valve in both directions between the hands.
• Apply fine abrasive paste to the valve face
and repeat the same steps.
NOTE:
Remove the paste from the valve face and
seat after each polishing work.
• Apply blue mechanic paint to the valve
face.
• Install the valve on the head.
• Press the valve against the seat through
the valve guide.
• Measure the valve seat width again. If
the seat width is out of specification, mill
and polish the valve again.
************************************

VALVES AND VALVE GUIDES

1. Measure:
• Stem – guide clearance
Stem – guide clearance =
Out of specification => Replace guide.
4-29
ENGINE
Internal guide diameter a
Stem diameter b
Stem – guide clearance:
Intake => 0.010~0.037 mm
<limit>: 0.08 mm
Exhaust: => 0.025~0.52 mm
<limit>: 0,10 mm
-