1971 Kawasaki F81M
Specifications and workshop reference information for the 1971 Kawasaki F81M, 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 | Air-cooled 2-stroke single-cylinder rotary valve |
| Displacement | 249 cc |
| Bore × Stroke | 69.0 mm × 66.8 mm |
| Compression Ratio | 7.0:1 |
| Maximum Power | Approx. 32 hp |
| Maximum Torque | — |
| Carburetor | Mikuni VM32 |
| Lubrication | Premix |
| Fuel Mix Ratio | 32:1 |
| Ignition | Magneto |
| Spark Plug | NGK B8ES |
| Spark Plug Gap | 0.6–0.7 mm |
Transmission
| Transmission Type | 5-speed constant mesh |
| Clutch | Wet multi-plate |
| Primary Reduction | 3.087 |
| Final Reduction | 3.000 |
| Overall Reduction | — |
Dimensions
| Overall Length | 2150 mm |
| Overall Width | 840 mm |
| Overall Height | 1180 mm |
| Wheelbase | 1435 mm |
| Ground Clearance | 290 mm |
| Fuel Tank Capacity | 9.0 L |
Chassis
| Frame Type | Steel double cradle |
| Caster Angle | 28° |
| Trail | 110 mm |
| Front Suspension | Telescopic forks |
| Rear Suspension | Twin shock swingarm |
| Front Suspension Travel | 200 mm |
| Rear Suspension Travel | 180 mm |
Brakes & Wheels
| Front Tire | 3.00-21 |
| Rear Tire | 4.00-18 |
| Front Brake | Drum |
| Rear Brake | Drum |
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