| MODEL | DUCATI 400SS JUNIOR 1989 - 1990 |
| Year | 1989 - 1990 |
| Engine Type | Four stroke, 90 degree L-twin cylinder, SOHC, desmodromic 2 valve per cylinder |
| Displacement / Capacity | 398 cc / 24.3 cu in |
| Bore X Stroke | 70.5 x 51 mm |
| Compression Ratio | 10.0:1 |
| Cooling System | Air cooled |
| Max Power | 30.9 kW / 42 hp @ 10000 rpm |
| Max Torque | 35.2 Nm / 26 ft-lb @ 8500 rpm |
| Ignition | Kokusan electronic |
| Induction | Mikuni CVK-V36 carburettor |
| Start System | Electric |
| TRANSMISSION SPECS | |
| Lubrication | — |
| Gear Box | 6 Speed |
| Clutch | — |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | — |
| Front Suspension | 41 mm Marzocchi inverted telescopic fork, M1BB |
| Rear Suspension | Cantilever swingarm, Marzocchi PBS1R monoshock, preload and rebound damping |
| Front Brakes | 2 x 280 mm discs |
| Rear Brakes | Single 260 mm disc |
| DIMENSION SPECS | |
| Overall Length | 2000 mm / 78.7 in |
| Overall Width | 670 mm / 26.4 in |
| Overall Height | 1160 mm / 45.7 in |
| Seat Height | 750 mm / 29.5 in |
| Wheelbase | 1450 mm / 57.1 in |
| Ground Clearance | — |
| Dry Weight | 174 kg / 384 lbs |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | 130/60 VR16 |
| Rear Tyre | 160/60 VR16 |
| FUEL SYSTEM | |
| Fuel Capacity | 17 L / 4.5 US gal / 3.7 Imp gal |
| Fuel Consumption | — |
| Top Speed | — |
First-generation 400 cc Supersport, a sleeved-down 750SS with the same trellis frame, intended for Japan's 400 cc class. Reviewers liked the chassis, brakes and ergonomics but found the engine peaky, the carburation troublesome and the rear shock too soft. A quirky small Ducati mostly for enthusiasts.
