1981 Kawasaki KX125 Specifications and Specs
Specifications and workshop reference information for the 1981 Kawasaki KX125, including engine, chassis, service data and setup details.
Note: Specs are compiled from factory data, manuals and owner feedback. Bikes vary — if yours is different, jump into the forum and share it.
General Specifications
| Engine Type | Liquid-cooled 2-stroke single-cylinder reed valve |
| Displacement | 124 cc |
| Bore × Stroke | 54.0 × 54.0 mm |
| Compression Ratio | 7.2:1 |
| Maximum Power | 27 hp |
| Maximum Torque | 19 Nm |
| Carburetor | Mikuni VM30SS |
| Lubrication | Premix |
| Fuel Mix Ratio | 20:1 |
| Ignition | CDI |
| Spark Plug | NGK B9ES |
| Spark Plug Gap | 0.6 – 0.7 mm |
Transmission
| Transmission Type | 6-speed manual |
| Clutch | Wet multi-plate |
| Primary Reduction | 3.090 |
| Final Reduction | 3.714 |
| Overall Reduction | 11.48 |
Dimensions
| Overall Length | 2110 mm |
| Overall Width | 835 mm |
| Overall Height | 1160 mm |
| Wheelbase | 1400 mm |
| Ground Clearance | 300 mm |
| Fuel Tank Capacity | 8.5 L |
Chassis
| Frame Type | Steel single cradle |
| Caster Angle | 28° |
| Trail | 113 mm |
| Front Suspension | Kayaba telescopic forks |
| Rear Suspension | Uni-Trak single shock |
| Front Suspension Travel | 240 mm |
| Rear Suspension Travel | 250 mm |
Brakes & Wheels
| Front Tire | 2.75-21 |
| Rear Tire | 4.10-18 |
| Front Brake | Drum brake |
| Rear Brake | Drum brake |
125cc Other Specs
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