Yamaha TW200 Service Manual page 99

INSPECTION AND REPAIR
I
ENG
I' ..
I
INSPECTION AND REPAIR
CYLINDER HEAD
1. Eliminate:
- Carbon deposit
(from combustion chamber)
Use rounded scraper.
CD.
NOTE: _
Do not use a sharp instrument and avoid damage-
ing or scratching:
-Spark plug threads
-Valve seat
2. Inspect:
-Cylinder head
Scratches/ Damage
~
Replace.
3. Measure:
-Warpage
Out of
specification~Resurface.
Cylinder Head Warpage:
Less than 0.03 mm (0.0012 in)
4. Resurface:
-Cylinder head
Resurfacement steps:
- Place a 400 - 600 grit wet sandpaper on the
surface plate, and resurface the head using
figure-eight sanding pattern.
NOTE: _
Rotate the head several times to avoid remov-
ing too much material from on side.
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