Yamaha YZF-R125 Service Manual: Removing the piston
1. Remove:
-
Piston pin clips "1"
-
Piston pin "2"
-
Piston "3"
| CAUTION: Do not use a hammer to drive the piston pin out. |
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 crankcase.
-
Before removing the piston pin, deburr the piston pin clip groove and the piston 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 "4".
2. Remove:
-
Top ring
-
2nd ring
-
Oil ring
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.
Checking the cylinder and piston
1. Check:
Piston wall
Cylinder wall
Vertical scratches Replace the
cylinder,
and replace the piston and piston rings as a
set.
2. Measure:
Piston-to-cylinder clearance
a. Mea ...
Other materials:
Checking the drive sprocket
1. Check:
Drive sprocket
More than 1/4 tooth "a" wear
Replace the
drive chain sprockets as a set.
Bent teeth Replace the drive
chain sprockets
as a set.
b. Correct
1. Drive chain roller
2. Drive chain sprocket
Checking the rear wheel sprocket
Refer to "CHECKING AND R ...
Checking the front brake master cylinder
1. Check:
Brake master cylinder
Damage/scratches/wear Replace.
Brake fluid delivery passages
(brake master cylinder body)
Obstruction Blow out with
compressed air.
2. Check:
Brake master cylinder reservoir
Cracks/damage Replace the brake
master
cylinder.
Brake maste ...
Checking the cylinder and piston
1. Check:
Piston wall
Cylinder wall
Vertical scratches Replace the
cylinder,
and replace the piston and piston rings as a
set.
2. Measure:
Piston-to-cylinder clearance
a. Measure cylinder bore "C" with the cylinder
bore gauge.
NOTE:
Measure cylinder bore "C" by takin ...