1976 Ossa Phantom 250 GP Specifications and Specs
Specifications and workshop reference information for the 1976 Ossa Phantom 250 GP, including engine, chassis, service data and setup details.
Photo credit:
VMX Re-Creations
– Vintage Ossa 250 GP restoration
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 |
| Displacement | 244 cc |
| Bore × Stroke | 72.0 mm × 60.0 mm |
| Compression Ratio | 10.5:1 (approx.) |
| Maximum Power | 32 hp (approx.) |
| Maximum Torque | N/A |
| Carburetor | Bing / Amal 32–36 mm | Replacement Options |
| Lubrication | Premix |
| Fuel Mix Ratio | 25:1 – 32:1 | Premix Calculator |
| Ignition | Motoplat magneto |
| Spark Plug | NGK B8ES |
| Spark Plug Gap | 0.6 – 0.7 mm |
Transmission
| Transmission Type | 5-speed manual |
| Clutch | Wet, multi-plate |
| Primary Reduction | N/A |
| Final Reduction | Chain drive |
| Overall Reduction | N/A |
Dimensions
| Overall Length | N/A |
| Overall Width | N/A |
| Overall Height | N/A |
| Wheelbase | 1400 mm (approx.) |
| Ground Clearance | 300 mm (approx.) |
| Fuel Tank Capacity | 9 L (approx.) |
| Bearing Sizes |
Bearing Finder |
Chassis
| Frame Type | Single cradle steel frame |
| Caster Angle | N/A |
| Trail | N/A |
| Front Suspension | Betor telescopic forks | Fork Oil Levels |
| Rear Suspension | Twin shock (Betor) |
| Front Suspension Travel | 200 mm (approx.) |
| Rear Suspension Travel | 110 mm (approx.) |
Brakes & Wheels
250cc Other Specs
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