Category:
Lightweight dual-sport motorcycle, popular for trail riding, off-road use, and light street commuting.
Target Audience:
Young riders, off-road enthusiasts, and those seeking an economical and versatile small-displacement motorcycle.
Competitors:
Honda CR125R (off-road), Yamaha DT125, Suzuki RM125 (off-road variants), and other 125cc dual-purpose/off-road bikes of the era.
Off Road Capability:
Long-travel suspension, knobby tires, high ground clearance, and agile chassis designed for off-road terrain.
Street Legality:
Equipped with lights, horn, and mirrors for street use, making it a true dual-purpose machine.
Engine Character:
Known for its punchy two-stroke powerband, offering exciting performance for its displacement.
Value Proposition:
Essential for owners and mechanics to maintain, diagnose, and repair the KMX125, ensuring longevity and optimal performance.
Years Covered:
1986, 1987, 1988, 1989, 1990
Region Coverage:
Global (primary focus on typical specifications for these model years)
Type:
Workshop Service Manual
Purpose:
Primary use for mechanical technicians and qualified mechanics
Engine:
Full engine disassembly, assembly, tuning, and troubleshooting (including top-end, bottom-end, cooling, lubrication).
Transmission:
Gearbox inspection, disassembly, assembly, clutch service, and adjustment procedures.
Fuel System:
Carburetor (likely Keihin PWK series for this era) disassembly, cleaning, tuning, and fuel tank/petcock maintenance.
Electrical System:
Ignition system (CDI, coil, spark plug), lighting, charging system (alternator, battery), and wiring diagrams.
Cooling System:
Liquid cooling system maintenance, radiator, thermostat, and coolant fluid specifications.
Suspension:
Front fork (telescopic) service, seal replacement, oil levels, and rear shock absorber inspection and adjustment.
Brakes:
Front disc brake and rear drum brake service, hydraulic system bleeding, pad/shoe replacement, and adjustment.
Frame And Bodywork:
Chassis inspection, seat, fenders, fuel tank removal/installation, and general body panel maintenance.
Wheels And Tires:
Wheel bearing service, spoke tensioning, tire replacement, and recommended tire pressures.
Maintenance:
Scheduled maintenance intervals, oil changes, filter replacements, chain adjustment, spark plug checks, and carburetor cleaning.
Troubleshooting:
Diagnostic charts and procedures for common starting, running, and electrical issues.
Repair:
Step-by-step instructions for component removal, replacement, and reassembly for all major systems.
Tuning And Adjustment:
Carburetor jetting, ignition timing checks (where applicable), suspension setup, and chain/brake adjustments.
Depth Level:
Comprehensive (covering from basic maintenance to complete engine rebuilds and electrical diagnostics).
Diagnostic Capability:
Includes detailed troubleshooting flowcharts and symptom-based problem diagnosis.
Special Tools:
Likely specifies necessary special tools for specific procedures, such as clutch holding tools or specialized pullers.
Engine Type:
Liquid-cooled, 2-stroke, single-cylinder
Displacement:
124 cc (approximate, often cited as 123.6 cc)
Bore X Stroke:
56.0 x 50.6 mm
Compression Ratio:
7.1:1 (typical for this era, may vary slightly)
Power Output:
Approx. 16-18 hp (at crank, depending on region and tuning)
Torque:
Approx. 1.3 kgf-m / 12.7 Nm (at 7,500 rpm, approximate)
Top Speed:
Approx. 100-115 km/h (62-71 mph), rider and conditions dependent
Carburetor:
Keihin PWK30 (typical, single downdraft carburetor)
Fuel Type:
Unleaded gasoline (minimum 91 octane recommended)
Fuel Capacity:
9.5 Liters (including reserve)
System:
Kawasaki K-ASE (Kawasaki Automatic Super-lube Engine) oil injection system
Oil Type:
2-stroke engine oil (API TC, JASO FD or higher)
Type:
6-speed, constant mesh
Clutch:
Wet, multiple disc
Gear Ratios:
1st: 2.500 (30/12), 2nd: 1.875 (30/16), 3rd: 1.400 (28/20), 4th: 1.136 (25/22), 5th: 0.958 (23/24), 6th: 0.833 (20/24)
Transmission Oil:
API GL-3 or GL-4 SAE 80W gear oil
Transmission Oil Capacity:
Approx. 0.8 Liters
Crash Test Results:
N/A (Motorcycles are not subject to the same crash testing standards as cars).
Braking System:
Front: Disc brake, Rear: Drum brake (basic but effective for its class).
Lighting:
Headlight, taillight, brake light, turn signals (essential for street legality).
Frame Construction:
Steel double-cradle frame for rigidity and durability.
Ergonomics:
Designed for an upright riding position, aiding rider control off-road.
Infotainment System:
N/A (Basic motorcycle, no electronic infotainment systems).
Assistance Systems:
N/A (No electronic driver assistance features).
Connectivity Features:
N/A
Ignition System:
CDI (Capacitor Discharge Ignition) system for reliable spark.
Cooling Type:
Liquid cooling system for improved temperature regulation and consistent performance.
Oil Change Interval:
Every 3,000 km or 6 months, whichever comes first (transmission oil).
Air Filter Cleaning:
Every 1,000 km or as needed based on conditions.
Spark Plug Check:
Every 1,000 km. Replacement as needed.
Chain Maintenance:
Lubricate and adjust chain tension every 500 km or as needed.
Brake Fluid Check:
Check and top-up as needed. Flush and replace every 2 years.
Engine Oil:
Kawasaki K-ASE 2-stroke oil (or equivalent JASO FD/API TC rated oil).
Transmission Oil:
SAE 80W API GL-3 or GL-4 gear oil.
Coolant:
Permanent type antifreeze (ethylene glycol based) mixed with distilled water at a 50:50 ratio.
Brake Fluid:
DOT 3 or DOT 4 brake fluid.
Power Valve Sticking:
Common on high-mileage two-strokes, requiring cleaning and lubrication of the power valve mechanism.
Carburetor Fouling:
Can occur due to improper fuel/oil mixture or infrequent use, requiring thorough cleaning.
Suspension Leaks:
Fork seals and rear shock seals can degrade over time, leading to oil leaks.
Electrical Connections:
Corrosion on electrical connectors can lead to intermittent issues, requiring cleaning and dielectric grease.
Genuine Parts:
May be limited for older models, but many aftermarket parts are available.
Kawasaki Legacy:
Kawasaki has a long and storied history in motorcycle manufacturing, known for performance and innovation, particularly in the off-road and sportbike segments.
Kmx Lineage:
The KMX series was Kawasaki's entry into the competitive 125cc dual-purpose market, offering a blend of off-road prowess and on-road usability, evolving from earlier models like the KE125 and G5.
Manufacturing Period:
The KMX125 was produced through the late 1980s and early 1990s, with significant updates during its run.
Manufacturing Location:
Primarily manufactured in Japan.
Motorcycle Awards:
While specific awards for the KMX125 are not widely publicized, it was a well-regarded and popular model in its segment during its production run, known for its spirited performance and versatility.
Owner Satisfaction:
Generally positive among enthusiasts for its fun factor and off-road capability, despite its age.
Emissions Certification:
Met the emissions standards of its time for its respective markets.
