Honda CRF450X User Manual

Valve Clearance
66 Servicing Your Honda
Cylinder Head Cover Removal
Before inspection, clean the engine thoroughly to
keep dirt from entering the engine.
1. Remove the seat (page 36).
2. Remove the fuel tank (page 37).
3. Disconnect the breather tube (1) and spark
plug cap (2).
5. Remove the plug hole packing and cylinder
head cover packing.
Positioning At Top Dead Center On The
Compression Stroke
1. Remove the crankshaft hole cap (1).
(1) breather tube (2) spark plug cap
4. Remove the cylinder head cover A bolt (3),
cylinder head cover B bolts (4) and cylinder
head cover (5).
(3) cylinder head cover A bolt
(4) cylinder head cover B bolts
(5) cylinder head cover
(1) crankshaft hole cap
(2)
(1)
(4)
(5)
(3)
(1)
Refer to Safety Precautions on page 25.
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 the valve
clearance when the engine is cold at the intervals
specified in the Maintenance Schedule.
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.

Honda CRF450X Specifications

General

Engine Type	449cc liquid-cooled single-cylinder four-stroke
Bore x Stroke	96.0mm x 62.1mm
Compression Ratio	12.0:1
Induction	Programmed Fuel Injection (PGM-FI), 46mm throttle body
Front Brake	Single 240mm disc with twin-piston caliper
Rear Brake	Single 240mm disc
Front Tire	80/100-21
Rear Tire	110/100-18
Wheelbase	58.3 inches
Fuel Capacity	2.0 gallons
Final Drive	#520 chain; 13T/51T
Front Suspension	49mm leading-axle inverted telescopic Showa fork; fully adjustable
Rear Suspension	Pro-Link Showa single shock with spring preload adjustability
Trail	4.6 inches
Curb Weight	275 pounds (Includes all standard equipment, required fluids and a full tank of fuel—ready to ride)
Rake	27.0°