Honda CRF450X 2020 Owner's Manual & Competition Handbook page 91

Valve Clearance Inspection
1. Set the piston at TDC on the compression
stroke (page 82).
2. Measure the intake valve clearances by
inserting a feeler gauge (1) between the intake
rocker arms (2) and camshaft cam lobes (3).
NOTICE
Be careful not to damage the intake rocker arms.
(2)
(1)
(3) (1)
(2)
(1) feeler gauge (3) camshaft cam lobes
(2) intake rocker arms
Valve Clearance:
IN: 0.004 ± 0.001 in (0.11 ± 0.03 mm)
3. Measure the exhaust valve clearances by
inserting a feeler gauge (1) between the
exhaust rocker arms (4) and shims (5).
(4)
(5)
(3)
(1)
(4)
(5)
(1)
(1) feeler gauge
(4) exhaust rocker arms
Valve Clearance:
EX: 0.011 ± 0.001 in (0.28 ± 0.03 mm)
(3)
If intake valve clearance and exhaust valve
clearance need adjustment, see Camshaft Removal
(this page) and select the correct shim for each
valve.
Camshaft Removal
1. Record the intake valve and exhaust valve
2. Remove the cam chain tensioner lifter cover
(5)
(1) cam chain tensioner lifter cover bolt
(2) sealing washer
(4)
(5) valve shims
Valve Clearance
clearances (this page).
Make sure the piston is at TDC on the
compression stroke (page 82).
bolt (1) and sealing washer (2).
(2)
Servicing Your Honda
(1)
(cont'd)
83