Honda CRF450R 2009 Service Manual page 255

Measure the height of each cam
lobe
SERVICE LIM ITS :
IN : 37.52
mm
(1.477
in)
EX: 28.58 mm (1.125 in)
NOTE '
Check the rocker arm
if
the cam lobe is worn or
damaged.
OECOMPRESSOR SYSTEM
Make sure of the plunger operation using the fonowing
procedure:
1. Move the decompressor weight outward with your
finger.
- The plunger operation is normal if it is retracted.
2. Release the decompressor weight.
- The decompressor weight should move inward
automatically.
- The plunger operation is normal
if
II is protruded.
If the decompressor weight and plunger operation is
abnormal, disassemble and
dean
the derompressor
system and camshaft (page 9-13).
Replace the damaged parts jf necessary
CAMS HAFT HOLDER
Check the set ring grooves for scoring or scratchers.
Check the camshaft holder for installalion of the dowel
pins
DECOMPRESSOR SYSTEM
DISASSEMBLY
Remove the camshaft (page 9-10).
Release the spring end from the decompressor weight.
Turn the decompressor weight as shown and remove
the camshaft bearing.
CYLINDER HEADNALVES
'09 shown:
·09 shown:
WEIGHT
DOWEL PINS
GROOVES
'09 shown: WEIGHT BEARING
SPRING END
9-13