Segment:
High-performance Motocross Competition Motorcycle.
Target Audience:
Motocross racers, performance enthusiasts, and DIY mechanics seeking in-depth maintenance and repair knowledge.
Competitors:
Yamaha YZ450F, Kawasaki KX450F, Suzuki RM-Z450, KTM 450 SX-F.
Engine Design:
Known for its potent four-stroke power delivery and compact engine design.
Suspension Performance:
Features advanced suspension systems designed for aggressive off-road riding.
Handling Characteristics:
Renowned for its agile handling and rider-friendly ergonomics.
Engine:
Complete engine disassembly, inspection, repair, and reassembly.
Transmission:
Gearbox operation, maintenance, and repair.
Fuel System:
Carburetor tuning, maintenance, and overhaul (including pilot jet, mixture screw adjustments).
Ignition System:
Stator, magneto, coil, spark plug diagnosis and replacement, troubleshooting 'no spark' conditions.
Suspension:
Front forks, rear shock (struts), linkage, swingarm maintenance and adjustment.
Brakes:
Front and rear brake systems, including rotors, pads, hydraulic lines.
Electrical System:
Wiring schematics, charging system (rectifier, battery), lighting, switches, starter system (kickstart).
Frame And Body:
Frame inspection, panels, fenders, plastic components, handlebars, seat.
Wheels And Tires:
Wheel bearings, tire replacement, spoke tension, wheel dimensions.
Cooling System:
Radiator, coolant, fluid replacement.
Lubrication System:
Oil types, capacities, and change intervals.
Troubleshooting:
Comprehensive guide for common problems and diagnostic procedures (e.g., no spark, starting issues).
Type:
Service Manual / Repair Manual
Format Description:
Digital Downloadable PDF
Primary Language:
English
Digital Features:
Clickable Chapters, Searchable Text
Restrictions:
No restrictions on printing or saving
Core Powertrain:
Engine internal components (crankshaft, connecting rod, piston, cylinder, valves, cams), gearbox, clutch.
Chassis Dynamics:
Front suspension (forks), rear suspension (shock, swingarm, linkage), steering head, triple trees.
Control Systems:
Brake calipers, master cylinders, levers, throttle cable, gearshift linkage.
Electrical Ancillary:
Ignition coil, CDI unit, lighting circuits, horn, battery charging circuit.
Disassembly Reassembly:
Complete tear down and rebuild procedures for all major components.
Maintenance Checks:
Regular service checks, fluid level checks, lubrication points.
Adjustments:
Valve clearance adjustment, carburetor mixture and idle speed adjustment, suspension sag adjustment.
Troubleshooting Diagnostics:
Step-by-step diagnostic guides for common performance issues and component failures.
Part Replacement:
Detailed instructions for replacing wear items and faulty components.
Specifications Settings:
Torque specifications for all fasteners, engine timing, suspension settings.
Level:
Comprehensive (covering routine maintenance to full engine rebuilds).
Illustrations Diagrams:
Includes pictures and detailed part diagrams for visual guidance.
Configuration:
Single-cylinder, SOHC, 4-valve.
Displacement:
449 cc (27.4 cu in)
Bore X Stroke:
96.0 mm x 62.1 mm (3.78 in x 2.44 in)
Cooling System:
Liquid-cooled
Compression Ratio:
Approx. 12.5:1 (exact spec may vary slightly by year/region)
Horsepower Estimate:
Estimated 55-60 HP (at crankshaft, actual may vary)
Torque Estimate:
Estimated 40-45 lb-ft (at crankshaft, actual may vary)
Carburetor Type:
Keihin FCR 37mm flat-slide carburetor
Fuel Type:
Unleaded gasoline, 91 octane or higher recommended.
Overall Length:
Approx. 83.0 in (2108 mm) - may vary slightly by year
Overall Width:
Approx. 32.5 in (825 mm) - may vary slightly by year
Overall Height:
Approx. 50.0 in (1270 mm) - may vary slightly by year
Dry Weight:
Approx. 216 lbs (98 kg) - may vary slightly by year
Fuel Capacity:
2.2 US gal (8.3 L)
Wheelbase:
Approx. 58.1 in (1475 mm) - may vary slightly by year
Oil Change:
Recommended every 10-15 hours of operation or annually, depending on usage.
Air Filter Cleaning:
Recommended after every few rides, or more frequently in dusty conditions.
Valve Clearance Check:
Recommended every 20-30 hours of operation, or as per manual schedule.
Spark Plug Replacement:
As needed or based on inspection and performance.
Engine Oil Type:
SAE 10W-30 API SG or higher (refer to manual for specific viscosity recommendations and brands).
Engine Oil Capacity:
Approximately 1.7 US qt (1.6 L) with filter change.
Coolant Type:
Honda HP Coolant or equivalent (50/50 mix of ethylene glycol and distilled water).
Carburetor Performance:
Can be sensitive to altitude and temperature changes, requiring occasional jetting adjustments. Pilot jet and mixture screw settings are crucial for optimal idle and low-speed performance.
Clutch Wear:
Clutch plates may require replacement due to aggressive riding conditions.
Suspension Seals:
Fork and shock seals can be prone to wear and leaks with heavy use.
Camchain Tensioner:
Some early models may benefit from checks or upgrades to the cam chain tensioner.
Motorsport Legacy:
Honda has a long and successful history in motorcycle racing, particularly in motocross.
Crf Line Introduction:
The CRF line represented a significant shift for Honda in the four-stroke motocross segment.
2002 Debut Impact:
The 2002 CRF450R was a groundbreaking model that quickly established itself as a class leader.
Manufacturing Location:
Primarily manufactured in Japan.
