Segment:
High-performance motocross competition bike
Target Audience:
Motocross racers, serious off-road riders, professional mechanics
Competitors:
Yamaha YZ450F, Honda CRF450R, Suzuki RM-Z450, KTM 450 SX-F
Engine Tech:
DOHC, 4-valve, liquid-cooled, four-stroke engine with fuel injection
Suspension Tech:
Advanced KYB PSF (Pneumatic Suspension Front) forks (later versions) and KYB shock, renowned for performance and tunability.
Chassis Design:
Lightweight aluminum twin-spar frame for optimal rigidity and handling
Target User Benefit:
Empowers users to perform complex diagnostics, repairs, and maintenance, reducing reliance on external service providers.
Engine:
Complete engine overhaul, top-end and bottom-end procedures, valve clearance, lubrication system, cooling system
Fuel System:
Fuel injection system (EFI), throttle body, fuel pump, injectors, fuel pressure testing
Transmission:
Clutch, gearbox, shift mechanism, lubrication
Drivetrain:
Final drive, chain and sprockets, hub maintenance
Chassis:
Frame, sub-frame, swingarm, linkage system
Suspension:
Front forks (KYB SSS - Speed Sensitive System), rear shock absorber (KYB), adjustment procedures, rebuilds
Brakes:
Front and rear brake systems, hydraulic lines, calipers, master cylinders, pad replacement, bleeding procedures
Electrical System:
Ignition system, lighting, charging system (stator, rectifier/regulator), battery, wiring diagrams, diagnostic codes (DTCs)
Cooling System:
Radiator, hoses, water pump, coolant specifications and capacity
Exhaust System:
Muffler, header pipe, servicing
Bodywork:
Plastics, seat, handlebars, controls, fairings
Maintenance:
Scheduled maintenance, oil changes, filter replacements, chain adjustment, air filter cleaning/replacement
Troubleshooting:
Diagnostic charts, common problems and solutions, fault finding
Repair:
Detailed step-by-step instructions for component removal, installation, and repair
Disassembly Assembly:
Complete breakdown and reassembly procedures for all major components
Adjustments:
Carburetor (if applicable, though this is EFI), clutch, throttle cable, suspension settings
Specifications Data:
Torque specifications, clearances, fluid capacities, performance data
Depth:
Comprehensive - suitable for professional technicians and experienced DIY mechanics
Diagnostic Capabilities:
In-depth diagnostics for EFI system, electrical faults, and mechanical issues
Rebuild Procedures:
Detailed instructions for complete engine and major component rebuilds
Configuration:
Single-cylinder, DOHC, 4-stroke
Displacement:
449 cc (27.4 cu. in.)
Bore X Stroke:
96.0 x 62.1 mm (3.78 x 2.44 in)
Cooling System:
Liquid-cooled
Valve Train:
DOHC, 4 valves
Horsepower:
Approx. 55-58 HP (at crankshaft, depending on dyno and specific tuning)
Torque:
Approx. 34-36 lb-ft (at crankshaft, depending on dyno and specific tuning)
Injection Type:
Digital Fuel Injection (DFI) with Keihin throttle body (e.g., 43mm)
Ignition:
Digital CDI with electronic advance
Type:
Constant mesh 5-speed sequential
Clutch:
Wet multi-disc, cable operated
Gear Ratios:
Specific ratios provided in manual (e.g., 1st: 2.571, 2nd: 1.933, 3rd: 1.579, 4th: 1.333, 5th: 1.150)
Final Drive Ratio:
Specific ratio provided in manual (e.g., 3.727 for 43/11 tooth sprockets)
Motocross Focus:
Designed for competition, safety features are focused on rider control and braking performance.
Brakes:
Powerful petal disc brakes (front and rear) for enhanced stopping power and heat dissipation.
Suspension:
High-performance suspension for stability and control over varied terrain.
Chassis Design:
Rigid frame for predictable handling.
Ergonomics:
Rider-centric ergonomics to promote control and reduce fatigue.
Engine Oil Change:
Every 10-15 hours of riding or as specified for racing conditions.
Air Filter Cleaning:
After every few hours of riding, especially in dusty conditions.
Spark Plug Replacement:
Refer to manual for specific interval, typically based on hours or performance.
Valve Clearance Check:
Initial check at 5-10 hours, then every 20-30 hours or as per manual. Crucial for EFI engines.
Engine Oil:
API SG, SF, SE, SH, SJ, SL, or SM; SAE 10W-40 (Kawasaki recommends specific KAWASAKI R4 10W-40)
Coolant:
High-quality coolant (50/50 mix of distilled water and ethylene glycol-based antifreeze) suitable for aluminum engines.
Transmission Oil:
Refer to manual; typically shares engine oil or requires specific transmission oil.
Fuel Injector Clogging:
Can occur with contaminated fuel; regular fuel filter checks and clean fuel are essential.
Suspension Seals:
Fork seal leaks can occur with heavy use; proactive maintenance is recommended.
Clutch Wear:
Normal wear item; slipping indicates need for replacement.
Efi System Diagnostics:
Requires specialized tools and knowledge for accurate troubleshooting; manual is crucial.
Kawasaki Motorsports:
Kawasaki has a long and successful history in professional motocross and supercross racing.
Kx Lineage:
The KX-F line has consistently been a front-runner, with continuous development in engine technology, suspension, and chassis design.
Year Specific Updates 2009:
The 2009 model saw significant updates, including a revised engine for improved low-to-mid range power and revised suspension settings.
Year Specific Updates 2010:
The 2010 model introduced further refinement, often with minor tweaks to ECU mapping, suspension, and bodywork for enhanced performance and rider feedback.
Manufacturing Location:
Japan
