| MODEL | YAMAHA XT 400 1981 - 1985 |
| Year | 1981 - 1985 |
| Engine Type | Four stroke, single cylinder, SOHC, 4 valve |
| Displacement / Capacity | 399 cc / 24.3 cu in |
| Bore X Stroke | 87 x 67.2 mm |
| Compression Ratio | 8.8:1 |
| Cooling System | Air cooled |
| Max Power | 22 kW / 31 hp @ 7000 rpm |
| Max Torque | 31.0 Nm / 3.2 kgf-m @ 6000 rpm |
| Ignition | CDI |
| Induction | Carburetor |
| Start System | Kick |
| TRANSMISSION SPECS | |
| Lubrication | — |
| Gear Box | 5 speed |
| Clutch | — |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | — |
| Front Suspension | Telescopic forks |
| Rear Suspension | Mono-cross |
| Front Brakes | Drum |
| Rear Brakes | Drum |
| DIMENSION SPECS | |
| Overall Length | 2260 mm / 88.9 in |
| Overall Width | 860 mm / 33.8 in |
| Overall Height | 1180 mm / 46.4 in |
| Seat Height | — |
| Wheelbase | 1405 mm / 55.3 in |
| Ground Clearance | 250 mm / 9.8 in |
| Dry Weight | 133 kg / 293.2 lbs |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | 3.00-21 |
| Rear Tyre | 4.60-18 |
| FUEL SYSTEM | |
| Fuel Capacity | 11.4 Litres / 3.0 US gal |
| Fuel Consumption | — |
| Top Speed | — |
The XT400 was a mid-size four-stroke trail and road bike with a four-valve air-cooled single and Mono-cross rear suspension. This early version used kick starting and drum brakes at both ends. It sat between the big XT500 and the smaller trail machines in Yamaha's dual-purpose range.
