| Engine | Yamaha WR250R | Yamaha WR450F |
|---|---|---|
| Displacement | 250 cc | 449 cc |
| Max power | 30 hp (@10 000 RPM) | 50 hp (@8 500 RPM) |
| Max torque | 23 Nm (@8 000 RPM) | 50 Nm (@7 500 RPM) |
| Redline | 11 500 RPM | 11 500 RPM |
| Idling speed | 1 200 RPM | 1 900 RPM |
| Management | Fuel Injection | Fuel Injection |
| Layout | DOHC Single | DOHC Single |
| Compression | 11.80:1 | 12.30:1 |
| Oil capacity | 1.40 litre | 1.00 litre |
| Oil type | 10W30, 10W40, YAMALUBE 10W40 | 10W40 |
| Spark plug type | NGK CR9EK | NGK CR8E |
| Cooling | Liquid | Liquid |
| Valves | 4 | 5 |
| Bore | 77.0 mm | 95.0 mm |
| Stroke | 53.6 mm | 63.4 mm |
| Throttle bore | 42.0 mm | |
| Weight to power | 2.48 kg/hp | |
| Power to weight | 403 hp/Ton | |
| Battery type | YTZ7S, 12V 6Ah | 12V 6Ah, YTZ7S (F) |
| Gearbox | Yamaha WR250R | Yamaha WR450F |
|---|---|---|
| Type | Sequential | Sequential |
| Clutch | Wet | Wet |
| Drive | Chain | Chain |
| Chain type | DAIDO 520VM2 114 links | |
| Gears count | 6 | 5 |
| Primary ratio | 3.12 | 2.652 |
| Final drive | 3.231 | 3.846 |
| 1. gear | 2.642 (53 km/h) | 2.417 (59 km/h) |
| 2. gear | 1.813 (77 km/h) | 1.733 (83 km/h) |
| 3. gear | 1.318 (106 km/h) | 1.313 (109 km/h) |
| 4. gear | 1.04 (134 km/h) | 1.05 (136 km/h) |
| 5. gear | 0.888 (157 km/h) | 0.84 (170 km/h) |
| 6. gear | 0.766 (182 km/h) |
| Chasis | Yamaha WR250R | Yamaha WR450F |
|---|---|---|
| Frame type | Semi double cradle | Bilateral beam aluminum |
| Front susp. | USD, 270.00 mm travel | 48mm USD, 300.00 mm travel |
| Rear susp. | Swingarm monoshock, 265.00 mm travel | Swingarm monoshock, 294.00 mm travel |