1981 Suzuki RM125
Specifications and workshop reference information for the 1981 Suzuki RM125, 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 | Single-cylinder, two-stroke, air-cooled |
| Displacement | 123 cc |
| Bore × Stroke | 54.0 × 54.0 mm |
| Compression Ratio | 6.5:1 |
| Maximum Power | ~23 hp |
| Maximum Torque | |
| Carburetor | Mikuni VM34SS |
| Lubrication | Premix |
| Fuel Mix Ratio | 32:1 |
| Ignition | CDI |
| Spark Plug | NGK B8ES |
| Spark Plug Gap | 0.5 – 0.6 mm |
Transmission
| Transmission Type | 6-speed constant mesh |
| Clutch | Wet multi-plate |
| Primary Reduction | 3.000 |
| Final Reduction | 3.538 |
| Overall Reduction | |
Dimensions
| Overall Length | 2,130 mm |
| Overall Width | 820 mm |
| Overall Height | 1,210 mm |
| Wheelbase | 1,430 mm |
| Ground Clearance | 320 mm |
| Fuel Tank Capacity | 7.5 L |
Chassis
| Frame Type | Steel single cradle |
| Caster Angle | |
| Trail | |
| Front Suspension | Telescopic forks |
| Rear Suspension | Full Floater single shock |
| Front Suspension Travel | |
| Rear Suspension Travel | |
Brakes & Wheels
| Front Tire | 2.75 – 21 |
| Rear Tire | 4.10 – 18 |
| Front Brake | Drum |
| Rear Brake | Drum |
125cc Other Specs
Community
VMX Owners Forum
Discuss vintage motocross bikes, restorations, tuning and riding.
