Honda CRF450X 2005 User Manual

TROUBLESHOOTING
Engine w ill not s tart
• Too much fuel getting to the engine
- Air cleaner clogged
- F looded carburetor
• Intake air leak
• Fuel contaminated / deteriorated
• No fuel to carburetor
- Fuel filter clogged
- Fuel line clogged
- Fuel valve stuck
- Float level misadjusted
- Fuel tank breather hose clogged
• Slow circuit clogged
• No spark at plug (faulty spark plug or ignition system malfunction) (page 4-12)
Le an mixture
• Fuel jets clogged
• Fuel tank breather hose clogged
• Fuel filter clogged
• Fuel hose restricted
• Float valve faulty
• Float level too low
• Air vent hose clogged
• Intake air leak
Misfiring during acceleration
• Ignition system faulty (page ' 8-5)
• lean mixture
Afterburn during acceleration
• Ignition system faulty (page 18-5)
• Lean mixture
• Accelerator pump faulty
Rich mixture
• Choke valve in the "ON" posi t ion
• F loat va lve faulty
• Float level t oo high
• Air jets clogged
• Air cleaner element contaminated
• Flooded carburetor
Engine s talls , hard to start , rough idling
• Fuel line restricted
• Ignition system mal fun ction (page 18-5)
• Low cylinder compression
• Fuel mixture too lean/ rich
• Fuel contaminated / deteriorated
• Intake air leak
• Float level
misadjusted
• Fuel tank breather hose clogged
~ • Pilot screw misadiusted
• Slow circuit or starting enric hm ent c ir cuit clogged
• Idle speed misadjusted
• Air cleaner clogged
Poor pe rformance (driveability) and poor fuel economy
• Fuel system clogged
• Ignition system faulty (page 18-5)
• Ai r cleaner clogged
Afterfiring
• Ignition system malfunction (page 18-5)
• Carburetor malfunction
• Lean mixture
• Rich mixture
FUEL SYSTEM
6-5

Honda CRF450X 2005 Specifications

General

Engine Type	449cc liquid-cooled single-cylinder four-stroke
Bore x Stroke	96.0mm x 62.1mm
Compression Ratio	12.0:1
Valve Train	Unicam, four-valve
Transmission	Wide-ratio five-speed
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
Seat Height	37.6 inches
Fuel Capacity	1.9 gallons
Ignition	Solid-state CD with electronic advance
Final Drive	520 O-ring-sealed chain
Front Suspension	47mm inverted Showa cartridge fork with 16-position rebound and 16-position compression damping adjustability; 12.4 inches travel
Rear Suspension	Pro-Link Showa single shock with spring preload, 17-position rebound damping adjustability, and compression damping adjustment separated into low-speed (13 positions) and high-speed (3.5 turns); 12.4 inches travel
Induction	Keihin 40mm flat-slide carburetor