1975 Yamaha DT400
Specifications and workshop reference information for the 1975 Yamaha DT400, 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 | 2-stroke, single-cylinder, air-cooled, piston port |
| Displacement | 397 cc |
| Bore × Stroke | 85.0 × 70.0 mm |
| Compression Ratio | 6.7:1 |
| Maximum Power | Approx. 34 hp |
| Maximum Torque | |
| Carburetor | Mikuni VM36 |
| Lubrication | Autolube (oil injection) or premix |
| Fuel Mix Ratio | 20:1 (if premix) |
| Ignition | CDI |
| Starter | Kick start |
| Spark Plug | NGK B8ES |
| Spark Plug Gap | 0.6–0.7 mm |
Transmission
| Transmission Type | 5-speed constant mesh |
| Clutch | Wet multi-plate |
| Primary Reduction | |
| Final Reduction | Chain drive |
| Overall Reduction | |
Dimensions
| Overall Length | 2200 mm |
| Overall Width | 900 mm |
| Overall Height | 1200 mm |
| Wheelbase | 1405 mm |
| Ground Clearance | 255 mm |
| Seat Height | 860 mm |
| Fuel Tank Capacity | 9.5 L |
| Dry Weight | Approx. 135 kg |
Chassis
| Frame Type | Steel cradle frame |
| Caster Angle | |
| Trail | |
| Front Suspension | Telescopic fork |
| Rear Suspension | Swingarm, dual shock |
| Front Suspension Travel | Approx. 200 mm |
| Rear Suspension Travel | Approx. 180 mm |
Brakes & Wheels
| Front Tire | 3.00-21 |
| Rear Tire | 4.00-18 |
| Front Brake | Drum |
| Rear Brake | Drum |
400cc Other Specs
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