Removing The Cylinder And Piston; Checking The Cylinder And Piston - Yamaha YZ85W1 Service Manual

CYLINDER HEAD, CYLINDER AND PISTON
EAS00253

REMOVING THE CYLINDER AND PISTON

1. Remove:
• piston pin clip
NOTE: NOTE:
Before removing the piston pin clip, cover the
crankcase opening with a clean rag to prevent
the piston pin clip from falling into the crank-
case.
2. Remove:
• piston pin
• piston
• small end bearing
CAUTION:
Do not use a hammer to drive the piston
pin out.
NOTE: NOTE:
Before removing the piston pin, deburr the pis-
ton pin clip's groove and the piston's pin bore
area. If both areas are deburred and the piston
pin is still difficult to remove, remove it with the
piston pin puller set
Piston pin puller set
90890-01304, YU-1304
3. Remove:
• piston ring
NOTE: NOTE:
When removing a piston ring, open the end
gap with your fingers and lift the other side of
the ring over the piston crown.
EAS00257

CHECKING THE CYLINDER AND PISTON

1. Check:
• piston wall
• cylinder wall
Vertical scratches → Replace the cylinder,
and the piston and piston rings as a set.
5-11
ENG
.