Positioning:
The Kawasaki KX series during this era were highly competitive motocross machines, known for their potent 2-stroke powerbands and agile handling. This manual targets owners and mechanics working on these performance-oriented off-road vehicles.
Competitors:
Primarily competed against Yamaha YZ125/YZ250, Honda CR125R/CR250R, and Suzuki RM125/RM250 models of the same period.
Features:
Instant access after payment, printable pages, lifetime replacement policy, digital format for easy on-trail access via smart devices.
Engine:
Complete disassembly, inspection, assembly, tuning, and troubleshooting of the 2-stroke engine (cylinder, piston, crankshaft, connecting rod, bearings, seals, reed valve assembly, power valve system).
Fuel System:
Carburetor (Mikuni VM series typically) overhaul, adjustment, jetting, fuel petcock, fuel lines, fuel tank maintenance.
Lubrication And Cooling:
Premix ratio recommendations, gearbox oil specifications and change intervals, coolant system (if applicable for specific radiator models).
Transmission:
Clutch assembly, gearbox disassembly/assembly, gear inspection, shift drum and forks, final drive chain and sprockets.
Suspension:
Front fork (USD - Upside Down forks) disassembly, seal replacement, oil type and level, damping adjustments, rear shock absorber overhaul, spring preload, damping adjustments.
Steering:
Steering head bearing inspection and adjustment, handlebar, controls.
Brakes:
Front and rear hydraulic disc brake systems, caliper overhaul, master cylinder, brake fluid specifications and bleeding procedures, pad replacement.
Electrical System:
Ignition system (CDI, spark plug), lighting (if applicable for specific versions), stator, rectifier/regulator, wiring diagrams, troubleshooting electrical faults.
Bodywork And Frame:
Frame inspection, seat, fenders, plastics, graphics, chain guard, footpegs.
Intake And Exhaust:
Airbox, air filter, exhaust system (silencer, pipe), packing material for silencer.
Routine Maintenance:
Pre-ride checks, oil changes, filter cleaning/replacement, chain adjustment, spark plug inspection, brake fluid checks.
Engine Overhaul:
Top-end rebuild (piston, rings), bottom-end rebuild (crankshaft, bearings), cylinder porting inspection.
Troubleshooting:
Diagnostic charts for common problems (engine not starting, loss of power, clutch slipping, suspension issues).
Assembly Disassembly:
Step-by-step instructions for removing and installing major components.
Technical Specifications:
Torque values for all fasteners, clearances, engine build specifications.
Depth:
Comprehensive, suitable for both DIY enthusiasts and professional mechanics. Covers detailed diagnostics and complete component rebuilds.
Engine Type:
Liquid-cooled, 2-stroke, single-cylinder
Displacement:
124 cc (approx.)
Bore X Stroke:
Typically around 56.0 x 49.8 mm
Compression Ratio:
Variable by year, often around 9.2:1 to 10.0:1
Power Valve System:
Kawasaki Integrated Power Valve System (KIPS) for improved low-to-mid range power delivery.
Engine Type:
Liquid-cooled, 2-stroke, single-cylinder
Displacement:
249 cc (approx.)
Bore X Stroke:
Typically around 66.4 x 72.0 mm
Compression Ratio:
Variable by year, often around 9.0:1 to 9.7:1
Power Valve System:
Kawasaki Integrated Power Valve System (KIPS) for improved low-to-mid range power delivery.
Carburetor Kx125:
Mikuni VM28SS (typical)
Carburetor Kx250:
Mikuni VM34SS (typical)
Fuel Type:
Unleaded gasoline (91 octane or higher recommended) mixed with 2-stroke oil (specified premix ratio, usually 20:1 or 32:1 depending on oil and application).
Rating Type:
N/A (Off-road competition vehicles are not typically rated by consumer safety organizations like NHTSA or Euro NCAP).
Braking System:
Hydraulic disc brakes front and rear for effective stopping power.
Protective Gear Recommendation:
The manual implicitly emphasizes the need for proper rider protection (helmet, goggles, boots, gloves, protective clothing) due to the nature of off-road riding.
Air Filter Cleaning:
Recommended every few rides or as conditions dictate (dusty environments require more frequent cleaning/replacement).
Spark Plug Inspection:
Recommended every 10-20 hours of operation, or if fouling is suspected.
Chain Lubrication And Adjustment:
Recommended every 500-1000 km, or every few rides depending on conditions.
Gearbox Oil Change:
Recommended every 15-25 hours of operation, or annually.
Engine Top End Rebuild:
Recommended every 20-40 hours of aggressive use (piston, rings).
Engine Bottom End Rebuild:
Recommended every 60-100 hours of aggressive use (crankshaft bearings, seals).
Fork Oil Kx125:
SAE 5W or 7.5W suspension fluid (e.g., Showa SS-05, KYB KSH 7.5) - specific weight varies by year and tuning needs.
Fork Oil Kx250:
SAE 5W or 7.5W suspension fluid - specific weight varies by year and tuning needs.
Brake Fluid:
DOT 4 hydraulic brake fluid (e.g., Castrol DOT 4, Motul DOT 4).
Common Wear Items:
Clutch plates, piston rings, clutch springs, pivot bearings (swingarm, linkage), wheel bearings, steering head bearings, crank seals, power valve deposits.
Power Valve Maintenance:
Regular cleaning of the KIPS system is crucial to prevent sticking and maintain optimal performance.
Kawasaki Motorsports:
Kawasaki has a long and successful history in motorcycle racing, particularly in motocross and supercross, with the KX line being a cornerstone of their performance offerings.
Model Evolution Kx125 Kx250
Mid 90S Advancements:
The 1994-1998 period saw continuous refinement of the KX models, with updates to suspension, engine performance, chassis geometry, and styling to remain competitive in the highly aggressive motocross market.
Manufacturing Location:
Primarily Japan, with potential assembly in other regions.
