Honda CRF450R Owner's Manual page 43

Remove the dowel pins, cylinder head gasket and cam
chain guide.
CAUTION:
Do not let the dowel pins and cam chain fall into
•
the crankcase.
(1) DOWEL PINS
(2) CYLINDER HEAD GASKET
(3) CAM CHAIN GUIDE
Cylinder Removal
Remove the cylinder bolt and cylinder.
CAUTION:
• Do not let the cam chain fall into the crankcase.
• Do not pry on or strike the cylinder.
(1) CYLINDER BOLT
(2) CYLINDER
Remove the A dowel pins, B dowel pin and cylinder
gasket.
CAUTION:
Do not let the dowel pins fall into the crankcase.
•
(1) A DOWEL PINS
(2) B DOWEL PIN
(3) CYLINDER GASKET
Piston Removal
Place clean shop towels in the crankcase to keep the
piston pin clips, or other parts, from falling into the
crankcase.
Remove the piston pin clips using a pair of needle-nose
pliers.
Press the piston pin out of the piston, and remove the
piston.
CAUTION:
Do not damage the piston
•
Always support the piston when pressing out the
•
pin.
Do not let the clips fall into the crankcase.
•
NOTE:
• Under racing conditions, the piston and rings should
be replaced after 15.0 hours of running. Replace the
piston pin after 30.0 hours of running.
Spread each piston ring and remove by lifting it up at a
point just opposite the gap.
CAUTION:
• Do not damage the piston ring by spreading the
ends too far.
(1) PISTON PIN CLIP (2) PISTON PIN
(3) PISTON (4) PISTON RINGS
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