Yamaha PW80T Manual page 35

NOTE:
Break each nut loose ( 1 I 4 turn) prior to remov-
ing.
:BP6HS~F~
:~:
I
+
I
I I ~
I Plug gap I
~
10.6-0.7 mm I
I (0.024-0.028
in) I
L ___ - - -
\
\
\ \
\ \
\
\~
\\
"''
3. With the piston at top dead center, raise
the cylinder until the cylinder skirts clear
crankcase. Stuff a clean shop rag into
crankcase cavity, around rod, to prevent
dirt and other foreign particles from enter-
ing. Remove cylinder.
4. Remove the piston pin clip from the
piston. Push the piston pin out from op-
posite side. Remove the piston.
NOTE:
If the pin hangs up, use a piston pin puller. Do
not hammer on pin as damage to rod, piston
and bearing will result.
0.15-0.35 mm
(0.006-0.014 in)
End gap (Installed)
Maintenance
Cylinder head
UP
~~
Piston clearance:
0.033- 0.038 mm
(0.0013-0.0015 in)
1. Using a rounded scraper, remove car-
bon deposits from combustion chamber.
Take care to avoid damaging the spark
plug threads. Do not use a sharp instru-
ment. Avoid scratching the metal sur-
face.
2. Place the head on a surface plate. There
should be no warpage. Correct by resur-
facing. Place 400 - 600 grit wet emery
sandpaper on surface plate and re-sur-
face head using a figure-eight sanding
pattern. Rotate head several times to
avoid removing too much material from
one side.
3. Clean the spark plug gasket mating sur-
face throughly.
Cylinder
1. Using a rounded scraper, remove carbon
deposits from exhaust port.
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