Honda CRF450RX 2020 Owner's Manual & Competition Handbook page 91

Valve Clearance
13. Check that "T" mark (22) on the primary drive
gear (23) aligns with the index mark (24) on
the right crankcase cover.
(23)
(22) "T" mark
(23) primary drive gear
(24) index mark
14. Rotate the camshaft by rotating the crankshaft
clockwise several times.
Make sure the piston is at TDC on the
compression stroke (page 80).
86
Servicing Your Honda
15. Measure the intake and exhaust valve
clearances by inserting a feeler gauge (25).
Valve Clearance:
IN: 0.005 ± 0.001 in (0.13 ± 0.03 mm)
(24)
EX: 0.011 ± 0.001 in (0.28 ± 0.03 mm)
Intake side:
(22)
(25) feeler gauge
16. Install a new sealing washer (26) and tighten
the cam chain tensioner lifter cover bolt (27).
(26) sealing washer (new)
(27) cam chain tensioner lifter cover bolt
Exhaust side:
(25)
(25)
(27)
(26)
Crankshaft Hole Cap Installation
1. Install the spark plug (page 78).
2. Coat a new O-ring (1) with engine oil and
install it onto the crankshaft hole cap (2).
Apply grease to the crankshaft hole cap
threads. Install and tighten the crankshaft hole
cap to the specified torque:
11 lbf·ft (15 N·m, 1.5 kgf·m)
(2)
(1) O-ring (new)
(2) crankshaft hole cap
(1)