1975 Suzuki RM125M
Specifications and workshop reference information for the 1975 Suzuki RM125M, 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 | Two-stroke, air-cooled, single-cylinder |
| Displacement | 123 cc |
| Bore × Stroke | 54.0 × 54.0 mm |
| Compression Ratio | ~7.4:1 |
| Maximum Power | ~20 hp |
| Maximum Torque | ~16 Nm |
| Carburetor | Mikuni VM28SS |
| Lubrication | Premix |
| Fuel Mix Ratio | 20:1 |
| Ignition | Suzuki PEI (CDI) |
| Spark Plug | NGK B8ES |
| Spark Plug Gap | 0.5 – 0.8 mm |
Transmission
| Transmission Type | 5-speed constant mesh |
| Clutch | Wet multi-plate |
| Primary Reduction | ~3.090 |
| Final Reduction | ~3.846 |
| Overall Reduction | ~11.88 |
Dimensions
| Overall Length | ~2050 mm |
| Overall Width | ~820 mm |
| Overall Height | ~1120 mm |
| Wheelbase | ~1350 mm |
| Ground Clearance | ~300 mm |
| Fuel Tank Capacity | 5.0 L |
Chassis
| Frame Type | Steel single cradle |
| Caster Angle | ~62° |
| Trail | ~100 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 |
125cc Other Specs
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