1973 Ossa 250 Phantom Specifications and Specs
Specifications and workshop reference information for the 1973 Ossa 250-Phantom, 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 |
| Displacement | 244 cc |
| Bore × Stroke | 70 × 64 mm |
| Compression Ratio | Approx. 11.0:1 |
| Maximum Power | ~30 hp |
| Maximum Torque | 17.7 lb-ft (24 Nm) |
| Carburetor | Amal 32 mm | Replacement Options |
| Lubrication | Premix |
| Fuel Mix Ratio | 25:1 | Premix Calculator |
| Ignition | Motoplat |
| Spark Plug | NGK equivalent |
| Spark Plug Gap | 0.5 – 0.6 mm |
Transmission
| Transmission Type | 5-speed constant mesh |
| Clutch | Wet multi-plate |
Dimensions
| Overall Length | 82 inches (2083 mm) |
| Overall Width | 85.5 cm (approximately 33.7 in) |
| Overall Height | 1,110 mm to 1,160 mm (44 to 45 inches). |
| Wheelbase | 1400 mm |
| Ground Clearance | 11.5 inches (approximately 290 mm). |
| Fuel Tank Capacity | 8 L |
| Bearing Sizes |
Bearing Finder |
Chassis
| Frame Type | Steel, twin shock |
| Front Suspension | Betor telescopic forks | Fork Oil Levels |
| Rear Suspension | Twin shock |
| Front Suspension Travel | 180 mm |
| Rear Suspension Travel | 160 mm |
Brakes & Wheels
250cc Other Specs
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