Valve Clearance Inspection - Honda CRF250R 2006 Owner's Manual

3. Rotate the crankshaft by turning the primary
drive gear bolt (3) (crankshaft) clockwise until
aligning the "punch" mark (4) on the primary
drive gear with the index mark (5) on the right
crankcase cover. In this position, the piston may
either be on the compression or exhaust stroke.
If the crankshaft passed the "punch" mark,
rotate the primary drive gear bolt clockwise
again and align the "punch" mark with the
index mark.
The inspection must be made when the piston
is at the top of the compression stroke when
both the intake and exhaust valves are closed.
This condition can be determined by moving
the exhaust rocker arm (6). If it is free, it is an
indication that the valves are closed and that
the piston is on the compression stroke. If it is
tight and the valves are open, rotate the
primary drive gear lock bolt 360° and realign
the "punch" mark to the index mark.
(3)
(4)
(3) primary drive gear lock bolt
(4) "punch" mark
(6)
(6) exhaust rocker arm

Valve Clearance Inspection

1. Measure the intake valve clearance by
inserting a feeler gauge (1) between the valve
lifters (2) and intake cam lobe (3).
(1) feeler gauge
(2) valve lifters
(5)
(3) intake cam lobe
(5) index mark
(1)
(2)
(3)
Valve Clearance
2. Measure the exhaust valve clearance by
inserting a feeler gauge (1) between the
exhaust rocker arm (4) and shim (5).
(4)
(5)
(1)
(1) feeler gauge
(4) exhaust rocker arm
(5) exhaust valve shim
Valve Clearances:
IN: 0.005 ± 0.001 in (0.12 ± 0.03 mm)
EX: 0.011 ± 0.001 in (0.28 ± 0.03 mm)
If intake valve clearance and exhaust valve
clearance need adjustment, see Camshaft
Removal (page 58) and select the correct shim for
each valve.
Servicing Your Honda
57