Yamaha GT1 Service Manual page 30

ENBINE -
Piston
2)
3)
Checking and correcting scratches
on the piston
A
piston
showing signs of seizure will result
in noise and loss of engine power. It will also
cause damage to the cylinder wall.
lf a piston that has seized is used again without
correction, another seizure will develop in the
same area. Lightly sand the seizure "high spot"
on the piston with oil store or #400 sandpaper
until smooth.
Fig. 4-7-2
Removing carbon
Remove carbon accumulations on the piston
crown, using a screwdriver or a sawblade.
Fig. 4-7-3
-24-
Carbon and gum accumulations in the ring
groove will result in piston ring seizure.
Re-
move them from the ring groove.
Fig. 4-7-4
B. Piston Installation Direction
I nstal! the piston with the arrow mark on the crown
pointing forward (toward the exhaust port of the
cylinder).
Fig. 4-7-5