Honda 2009 CRF450X Owner's Manual & Competition Handbook page 84

Piston/Piston Rings/Piston Pin
Cylinder Removal
1. Disconnect the breather hose (1) from the
cylinder.
2. Remove the cylinder bolt (2) and cylinder (3).
NOTICE
Do not let the cam chain fall into the crankcase.
Do not pry on or strike the cylinder.
(2)
(3)
(1) breather hose (3) cylinder
(2) cylinder bolt
3. Remove the dowel pins (4) and cylinder
gasket (5).
NOTICE
Do not let the dowel pins fall into the crankcase.
(4)
(5)
(4) dowel pins
(5) cylinder gasket
78
Servicing Your Honda
HONDA O/M CRF450X (Eu) 3RMEY620 00X3R-MEY-6200
Piston Removal
1. Place clean shop towels in the crankcase to
keep the piston pin clips, or other parts, from
falling into the crankcase.
2. Remove the piston pin clips (1) using a pair of
needle-nose pliers.
3. Press the piston pin (2) out of the piston (3),
and remove the piston.
Under racing conditions, the piston and rings
(1)
should be replaced after 15.0 hours of running.
Replace the piston pin after 30.0 hours of running.
(3)
(1)
(1) piston pin clips (3) piston
(2) piston pin
Piston Ring Removal
Spread each piston ring (1) and remove by lifting
it up at a point just opposite the gap.
NOTICE
Do not damage the piston ring by spreading the
ends too far.
(2)
(1) piston ring
(1)