Valve Clearance - Honda CRF450R 2009 Owner's Manual & Competition Handbook

Valve Clearance

Refer to Safety Precautions on page 23.
Excessive valve clearance will cause noise and
eventual engine damage. Little or no clearance
will prevent the valve from closing and cause
valve damage and power loss. Check valve
clearance when the engine is cold at the intervals
specified in the Maintenance Schedule (page 25).
The checking or adjusting of the valve clearance
should be performed while the engine is cold.
The valve clearance will change as engine
temperature rises.
64
Servicing Your Honda
Cylinder Head Cover Removal
Before inspection, clean the engine thoroughly to
keep dirt from entering the engine.
1. Remove the seat and hang the fuel tank to the
left of the frame (pages 33, 34).
2. Disconnect the breather tube (1) and spark
plug cap (2).
(2)
(1) breather tube (2) spark plug cap
3. Remove the cylinder head cover socket bolts
(3), rubber seals (4) and cylinder head cover
(5).
(3)
(5)
(3) cylinder head cover socket bolts
(4) cylinder head cover rubber seals
(5) cylinder head cover
Positioning At TDC On The Compression
Stroke
1. Remove the crankshaft hole cap (1).
(1)
(1)
(1) crankshaft hole cap
2. Remove the spark plug (page 63).
3. Remove the cylinder head cover (page 64).
(4)