Honda CRF450R 2007 Service Manual

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Take care nor tD tilt Ream the valve gui de to rem ove any carbon build-
or lean the reamer up before measuring the gui de 1.0.
in t he guide while Insert the reamer from the comb u stion ch amber
reaming. side of the head and always rotate the r eamer clock-
wise.
TOOLS:
IN:
Valve guid e reamer , 5.5 mm 07984-2000001 or
07984·2000000
(U.S.A.only)
EX : Valve guide reamer , 5.0 mm 07984-MA60001or
07984 - MASOOOO
(U.S.A.only)
Measure and record each
valve guide 1.0.
STANDARD:
IN : 5.552 mm (0.2186 in)
EX : 5.052 mm (0.1989 in)
Subtract each valve stem 0.0. from the correspond-
ing guide I.D. to obtain the stem-ta-guide clearance .
STANDARD:
IN : 0.010 - 0.037 mm (0.0004 - 0.0015 in )
EX ; 0. 020 - 0. 047 mm (0.0008 - 0. 0019 in)
Reface the valve If the stem-to-guide clearance exceeds the service
sears whene ve r t ile limits, determine if a new guide with standard
valve guides are dimensions would bring the clearance within toler-
rep/aced (pa ge 9- ance. If so, replace the guides as necessary and
29 ). ream to fit.
If the stem-to-guide clearance exceeds the service
limi ts with new guides also, replace the valves and
guides .
VALVE GUIDE REPLACEMENT
Mark new valve guides at the proper depth (see
specification page
9-30) using a marker . Chill th e
new valve guides in a freezer for about 1 hour.
Using a Toren to Heat the cylinder head to 100 - 150"C (212 - 300"F)
heat t he cylind er with a hot plate or oven. Do not heat the cylinder
head may cause head beyond 160°C (320" F) . Use temperatu re indi ca -
warpage. tor sticks, available from welding supply stores, to
be sure the cylinder head is heated to the proper
temperature.
Support the cylinde r head and drive the valve
guides out of the cylinder head from the combus -
tion chamber side.
TOOLS:
IN: Valve guide remover , 5.5 mm 07742·0010100
EX : Valve guide remover, 5.0 mm 07942· MA60000
CYLINDER HEADIVALVES
VALVE GUIDE REAMER
VAILVE GUIDE REMOVER
9-29

Honda CRF450R 2007 Specifications

General

Brand	Honda
Model	CRF450R 2007
Category	Motorcycle
Language	English