Segment:
High-performance Motocross/Off-Road Competition
Target User:
Motocross racers, experienced off-road riders, mechanics
Competitors:
Yamaha YZ450F, Honda CRF450R, Suzuki RM-Z450, Kawasaki KX450F
Vehicle Focus:
Power, agility, track performance
Manual Value:
Essential for maintaining peak performance and reliability of a high-strung racing engine
Engine Mechanical:
Full disassembly, inspection, repair, and reassembly of all engine components
Engine Electrical:
Ignition system, starting system, charging system diagnostics
Fuel System:
Carburetor overhaul and tuning (likely Keihin FCR), fuel pump (if applicable)
Cooling System:
Radiator, hoses, water pump maintenance and repair
Lubrication System:
Oil pump, oil passages, oil filter maintenance
Disassembly Reassembly:
Complete engine teardown and rebuild procedures
Troubleshooting:
Diagnostic flowcharts and common issue resolution for engine performance problems
Maintenance:
Scheduled maintenance tasks, filter changes, fluid checks
Torque Specifications:
Torque values for all critical fasteners and components
Valve Adjustment:
Detailed instructions for valve clearance adjustment
Clutch Service:
Clutch plate replacement, spring inspection, hydraulic clutch system bleeding
Depth:
Comprehensive, covering internal engine components, timing, and tuning
Detail Level:
Detailed diagrams, step-by-step instructions, and specifications for expert-level repairs
Engine Type:
4-stroke, Single Cylinder, LC4
Bore X Stroke:
97.0 mm x 60.8 mm
Valvetrain:
SOHC, 4 Valves
Compression Ratio:
11.5:1 (typical for this generation)
Horsepower:
Approx. 50-55 HP (at crankshaft, estimated)
Torque:
Approx. 45-48 Nm (at crankshaft, estimated)
Carburetor:
Keihin FCR 41 MX (specific variant may apply)
Fuel Type:
Unleaded Gasoline (91-98 RON recommended)
Ignition System:
Digital CDI (Capacitive Discharge Ignition)
Oil Type:
SAE 10W-50 Synthetic Motorcycle Oil (API SG or higher, JASO MA)
Oil Capacity:
Approx. 1.1 Liters (without filter change), 1.2 Liters (with filter change)
Transmission Type:
5-speed Manual
Clutch Type:
Wet multi-plate, hydraulic actuation
Gear Ratios:
Specific ratios documented in the manual
Transmission Oil:
SAE 80W-90 Gear Oil (API GL-4)
Transmission Oil Capacity:
Approx. 0.8 Liters
Safety Certification:
Not Applicable (Competition Off-Road Vehicle)
Braking System Front:
Hydraulic disc brake, Brembo caliper (specific size)
Braking System Rear:
Hydraulic disc brake, Brembo caliper (specific size)
Frame:
Chromium-molybdenum steel trellis frame
Infotainment System:
Not Applicable (Competition Motocross Bike)
Driver Assistance Features:
None (Competition Motocross Bike)
Connectivity Features:
None (Competition Motocross Bike)
Engine Management System:
Basic ignition timing, no advanced electronic fuel injection or rider modes
Oil Change Interval:
Every 15-20 hours of operation or 6 months, whichever comes first (competition use)
Air Filter Cleaning:
After every ride or as needed based on dust conditions
Valve Check Interval:
Every 20-30 hours of operation
Spark Plug Replacement:
Every 40-50 hours of operation or as needed
Engine Oil Spec:
SAE 10W-50 Synthetic (API SG/SH/SJ/SL, JASO MA)
Transmission Oil Spec:
SAE 80W-90 Gear Oil (API GL-4)
Coolant Type:
Ethylene Glycol based antifreeze coolant (50/50 mix with distilled water)
Engine Wear:
Piston and ring wear at higher hours, potential cam chain tensioner issues
Clutch Slippage:
Can occur with aggressive riding and prolonged use, requires timely plate replacement
Carburetor Tuning:
Sensitivity to altitude and temperature changes, requiring proper jetting adjustments
