1977 Suzuki RM125B Specifications and Specs
Specifications and workshop reference information for the 1977 Suzuki RM125B, 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 | 7.6:1 |
| Maximum Power | ~21 hp |
| Maximum Torque | ~17 Nm |
| Carburetor | Mikuni VM32SS | Replacement Options |
| Lubrication | Premix |
| Fuel Mix Ratio | 20:1 | Premix Calculator |
| 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 | 11.9 |
Dimensions
| Overall Length | 2060 mm |
| Overall Width | 820 mm |
| Overall Height | 1130 mm |
| Wheelbase | 1360 mm |
| Ground Clearance | 305 mm |
| Fuel Tank Capacity | 6.0 L |
| Bearing Sizes |
Bearing Finder |
Chassis
| Frame Type | Steel single cradle |
| Caster Angle | 62° |
| Trail | 100 mm |
| Front Suspension | Telescopic forks | Fork Oil Levels |
| Rear Suspension | Twin shock swingarm |
| Front Suspension Travel | 210 mm |
| Rear Suspension Travel | 190 mm |
Brakes & Wheels
125cc Other Specs
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