Decompressor Clearance Inspection/Adjustment (05-07) - Honda CRF450X 2005 Service Manual

MAINTENANCE
Inspect and adjus t
the decompressor
CleBrBnCe while fhe
engine is cold
(be/ow 35"C/95'f).
4-18
DECOMPRESSOR CLEARANCE
INSPECTIONI ADJUSTMENT ('05 - ' 07)
Always inspect and adjust the decompressor clear-
ance after adjusting the r ight exhau st valve clear-
ance.
Remove the following:
- Cylinder head cover (page 9-7)
- Crankshaft hole cap (page 9-8)
Turn the crankshaft clockwise to align the punch
ma rk on the primary drive gear wi th the index mark
on the right crankcase cover. Make sure that the pis-
ton is at
TDC
(Top Dead Center) on the compression
stroke.
This position can be obtained by confirming that
there is slack in the rocker arms. If there is no slack,
rolate the crankshaft clockwise one full tu rn and
align the punch mark on the primary dr ive gear wi th
t he index mark on the right crankcase cover again.
Check that the index line on the cam sprocket aligns
with the "6." mark on the
camsh~ft
holder.
Measure the decompressor arm clearance by insert -
ing a feeler gauge between the decompressor lifter
arm adjuster and right side rocker arm .
DECQMPRESSQR CLEARANCE:
RIGHT SIDE EXHAUST VALVE CLEARANCE
+
0.35 mm (0.014 in)
EXAMPLE:
If measured ri ght exhaust valve clearan ce is 0.28
mm
(0.0 11
in ), decompressor clearance is;
0.28 mm (0.011 i n) ... 0.35 mm (0.014 in) '" 0.63 mm
(0.025 in)
If decompressor clearance needs adjustment, see
following procedure.
Measure the right exhaust valve clearance by insert-
ing a feeler gauge between the r ight side rocker arm
and shim.
VALVE CLEARANCE :
EX: 0.28
±
0.03 mm (0.011
±
0.001 in)
Pull out the feeler gauge between the rocke r arm
and shim.
INDEX MARK
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