Honda 2007 CR125R, Owner'S Manual

Page: 55 / 144

Cylinder System
Piston Removal
1. Place the shop towel in the crankcase.
2. Remove the piston pin clips (1) using a pair of
needle-nose pliers. Press the piston pin (2)
out of the piston (3), and remove the piston.
3. Remove the connecting rod small end bearing
(4).
Under racing conditions, the piston and ring
should be replaced after 7.5 hours of running.
Replace the piston pin and connecting rod small
end bearing after 22.5 hours of running.
(1) piston pin clip (4) connecting rod small
end bearing (2) piston pin
(5) piston ring (3) piston
4. Spread each piston ring (4) and remove by
lifting it up at a point just opposite the gap.
The piston ring may be damaged if the ends are
spread too far.
Cylinder Head/Cylinder Decarbonizing
1. Remove the carbon deposits from the cylinder
head (1) and piston dome.
Take care to avoid scratching the cylinder
head piston dome, or the head gasket surface.
(1) cylinder head
2. Clean carbon deposits from the exhaust port (2)
area.
(2) exhaust port
Cylinder/Piston/Piston Pin/Piston Ring
Inspection
We recommend you consult the Service Manual
or your Honda dealer for correct Service Limit
measurements.
NOTICE
Servicing Your Honda
51
(2)
(3)
(5)
(1)
(1)
(2)
(4)
*CR125R/49~59(31KSR620).qxd 5/6/05 2:05 PM Page 51