| MODEL | YAMAHA XJ 400Z 1983 |
| Year | 1983 |
| Engine Type | Four stroke, transverse four cylinder, DOHC, four valves per cylinder |
| Displacement / Capacity | 399 cc |
| Bore X Stroke | 54 x 53.6 mm |
| Compression Ratio | 10.5:1 |
| Cooling System | Liquid cooled |
| Max Power | 41 kW / 55 hp @ 11500 rpm |
| Max Torque | 3.5 kgf-m / 25.3 lb-ft @ 10000 rpm |
| Ignition | Transistorized CDI |
| Induction | Carburettor |
| Start System | Electric |
| TRANSMISSION SPECS | |
| Lubrication | — |
| Gear Box | 6 speed |
| Clutch | — |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | — |
| Front Suspension | Telescopic forks |
| Rear Suspension | Monocross, link type |
| Front Brakes | 2x discs |
| Rear Brakes | Single disc |
| DIMENSION SPECS | |
| Overall Length | — |
| Overall Width | — |
| Overall Height | — |
| Seat Height | — |
| Wheelbase | 1420 mm / 55.9 in |
| Ground Clearance | — |
| Dry Weight | 177 kg / 390.2 lbs |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | 90/90-18 |
| Rear Tyre | 110/90-18 |
| FUEL SYSTEM | |
| Fuel Capacity | 19 Litres / 5.0 US gal |
| Fuel Consumption | — |
| Top Speed | — |
The XJ400Z was Yamaha's liquid-cooled, four-valve 400 four of 1983, a high-revving machine with a different engine from the air-cooled XJ400 and Seca. It offered 55 hp from 399 cc, with twin front discs and a link-type Monocross rear shock.
