Service Information - Honda CRF450R 2009 Service Manual

SERVICE INFORMATION
GENERAL
CYLINDER/PISTON
This section covers maintenance of the cylinder and piston. These procedures can be done with the engine installed in the
frame.
Before disassembly, clean the engine thoroughly to prevent dirt from entering it.
Be careful not to damage the mating surfaces when removing the cylinder. For example, do not use a screwdriver to pry the
cylinder.
Clean all disassembled parts with cleaning solvent before inspection, use compressed air to dry the
parts.
Under racing conditions, the piston and piston rings should be replaced after every 6 races or about 15 hours of operation.
Replace the piston pin after every 12 races or about 30 hours of operation.
SPECIFICATIONS
piston ring
TOOL
Cam chain tensioner
h " o l ~ d~e~,
- - -- ,
070MG"{)010100
I
I or07AMG-001A100 (U .S.A. only)
Top
0.065 - 0.100 (0.0026 - 0.0039) 0 .12 (0 .004 )
0.20 - 0.70 (0.008 - 0.028)
0 .71 (0.028)
10-3