1983 Yamaha YZ250
Specifications and workshop reference information for the 1983 Yamaha YZ250, 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 | Liquid-cooled, 2-stroke, single-cylinder, Yamaha Power Valve System (YPVS) |
| Displacement | 246 cc |
| Bore × Stroke | 68 × 68 mm |
| Compression Ratio | 7.4–9.2:1 |
| Maximum Power | N/A |
| Maximum Torque | N/A |
| Carburetor | Mikuni VM38SS |
| Lubrication | Premix |
| Fuel Mix Ratio | 24:1 recommended |
| Ignition | CDI magneto |
| Spark Plug | Champion N-86 |
| Spark Plug Gap | 0.5–0.6 mm |
Transmission
| Transmission Type | Constant mesh, 5-speed |
| Clutch | Wet, multiple-disc |
| Primary Reduction | 2.625 / 63:24 |
| Final Reduction | 3.692 / 48:13 |
| Overall Reduction | N/A |
Dimensions
| Overall Length | 2,170 mm |
| Overall Width | 850 mm |
| Overall Height | 1,230 mm |
| Wheelbase | 1,470 mm |
| Ground Clearance | 335 mm |
| Fuel Tank Capacity | 8.5 L |
Chassis
| Frame Type | Semi double cradle |
| Caster Angle | 28° |
| Trail | 119 mm |
| Front Suspension | Telescopic fork |
| Rear Suspension | Swingarm Monocross suspension |
| Front Suspension Travel | 300 mm |
| Rear Suspension Travel | 320 mm |
Brakes & Wheels
| Front Tire | 90/80-21-4PR |
| Rear Tire | 140/80-18-4PR |
| Front Brake | Drum brake |
| Rear Brake | Drum brake |
250cc Other Specs
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