Honda CRF250R 2018 Owner's Manual page 75

Valve Clearance
3. Measure the valve clearances of each exhaust
valve by inserting a feeler gauge (1) between
the exhaust rocker arms (4) slipper surface and
camshaft cam lobes (3).
NOTICE
Be careful not to damage the exhaust rocker arms.
(1)
(4)
(4)
(1) feeler gauge (4) exhaust rocker arms
(3) camshaft cam lobes
Valve Clearance:
EX: 0.007 ± 0.001 in (0.19 ± 0.03 mm)
If intake valve clearance and exhaust valve
clearance need adjustment, see Camshaft Removal
(this page) and select the correct shim for each
valve.
70
Servicing Your Honda
Camshaft Removal
1. Remove the cam chain guide bolts (1) and cam
chain guide (2).
NOTICE
Do not let the cam chain guide bolts fall into the
crankcase.
(3)
(3)
(1)
(1) cam chain guide bolts
2. Rotate the crankshaft by turning the flywheel
(3) counterclockwise until the decompressor
weight (4) faces up as illustrated below.
(3)
(1)
(3) flywheel
3. Remove the cam sprocket bolt (5) of the intake
NOTICE
Do not let the cam sprocket bolt fall into the
crankcase.
(2)
(5)
(5) cam sprocket bolt
4. Rotate the camshaft by turning the flywheel
(2) cam chain guide
5. Remove the cam chain tensioner lifter cover
(6)
(4)
(6) cam chain tensioner lifter cover bolt
(4) decompressor weight
(7) sealing washer
camshaft.
and make sure the piston is at TDC on the
compression stroke (page 69).
bolt (6) and sealing washer (7).
(7)