1973 Yamaha DT3 250 Specifications and Specs
Specifications and workshop reference information for the 1973 Yamaha DT3-250, 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
| Model | Yamaha 250 DT3 |
| Weight (net) | 258 lbs (117 kg) |
Performance
| Max speed | 75 mph (120 km/h) or more |
| Fuel consumption | 94.1 mpg @ 31 mph (40 km/L @ 50 km/h) |
| Climbing ability | 35° |
| Turning radius | 78.7 in (2000 mm) |
| Braking distance | 49 ft @ 31 mph (15 m @ 50 km/h) |
Engine
| Model | DT1-F |
| Type | 2-stroke, gasoline, torque induction |
| Lubrication | Separate lubrication (Yamaha Autolube) |
| Cylinder | Single, forward inclined, 7 port |
| Displacement | 246 cc |
| Bore x Stroke | 70 x 64 mm |
| Compression ratio | 6.8:1 |
| Max power | 24 BHP @ 7000 rpm |
| Max torque | 18.3 ft-lbs @ 6000 rpm |
| Starting system | Primary-coupled kick starter |
| Ignition | Flywheel magneto |
Carburetor
Transmission
| Clutch | Wet, multiple-disk |
| Primary reduction | 63/21 (3.095) |
| Gearbox | Constant mesh, 5-speed |
| 1st | 2.533 |
| 2nd | 1.789 |
| 3rd | 1.304 |
| 4th | 1.000 |
| 5th | 0.766 |
| Final drive | Chain 44/14 (3.142) |
Dimensions
| Length | 2115 mm |
| Width | 890 mm |
| Height | 1170 mm |
| Wheelbase | 1390 mm |
| Ground clearance | 260 mm |
| Bearing Sizes |
Bearing Finder |
Chassis
| Frame | Tubular double loop |
| Front suspension | Telescopic fork | Fork Oil Levels |
| Rear suspension | Swinging arm |
| Front cushion | Coil spring, oil damper |
| Rear cushion | Coil spring, oil damper |
Brakes & Wheels
| Front brake | Internal expansion (right hand) |
| Rear brake | Internal expansion (right foot) |
| Front tire | 3.00-21-4PR | Tyre Size Guide |
| Rear tire | 4.00-18-4PR | Tyre Size Guide |
Electrical
| Dynamo | F2A-1B (Mitsubishi) |
| Battery | 6N4-2A-2 |
| Capacity | 6V 4Ah |
| Headlight | 6V 35W/35W |
| Indicators | 6V 17W |
| Tail light | 6V 17W / 5.3W |
| Meter light | 6V 3W x2 |
Tanks
| Fuel capacity | 2.5 US gal (9.5 L) |
| Oil capacity | 1.7 US qt (1.6 L) |
250cc Other Specs
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