| Engine | Yamaha WR450F | Yamaha WR250R |
|---|---|---|
| Displacement | 449 cc | 250 cc |
| Max power | 50 hp (@8 500 RPM) | 30 hp (@10 000 RPM) |
| Max torque | 36 lb ft (@7 500 RPM) | 16 lb ft (@8 000 RPM) |
| Redline | 11 500 RPM | 11 500 RPM |
| Idling speed | 1 900 RPM | 1 200 RPM |
| Management | Fuel Injection | Fuel Injection |
| Layout | DOHC Single | DOHC Single |
| Compression | 12.30:1 | 11.80:1 |
| Oil capacity | 0.95 quart | 1.33 quart |
| Oil type | 10W40 | 10W30, 10W40, YAMALUBE 10W40 |
| Spark plug type | NGK CR8E | NGK CR9EK |
| Cooling | Liquid | Liquid |
| Valves | 5 | 4 |
| Bore | 95.0 mm | 77.0 mm |
| Stroke | 63.4 mm | 53.6 mm |
| Throttle bore | 42.0 mm | |
| Weight to power | 5.47 lbs/hp | |
| Power to weight | 457 hp/2500lbs | |
| Battery type | 12V 6Ah, YTZ7S (F) | YTZ7S, 12V 6Ah |
| Gearbox | Yamaha WR450F | Yamaha WR250R |
|---|---|---|
| Type | Sequential | Sequential |
| Clutch | Wet | Wet |
| Drive | Chain | Chain |
| Chain type | DAIDO 520VM2 114 links | |
| Gears count | 5 | 6 |
| Primary ratio | 2.652 | 3.12 |
| Final drive | 3.846 | 3.231 |
| 1. gear | 2.417 (37 mph) | 2.642 (33 mph) |
| 2. gear | 1.733 (52 mph) | 1.813 (48 mph) |
| 3. gear | 1.313 (68 mph) | 1.318 (66 mph) |
| 4. gear | 1.05 (84 mph) | 1.04 (83 mph) |
| 5. gear | 0.84 (106 mph) | 0.888 (97 mph) |
| 6. gear | 0.766 (113 mph) |
| Chasis | Yamaha WR450F | Yamaha WR250R |
|---|---|---|
| Frame type | Bilateral beam aluminum | Semi double cradle |
| Front susp. | 48mm USD, 11.81 in travel | USD, 10.63 in travel |
| Rear susp. | Swingarm monoshock, 11.57 in travel | Swingarm monoshock, 10.43 in travel |