| MODEL | SUZUKI RM 400 1978 |
| Year | 1978 |
| Engine Type | Single cylinder, two-stroke |
| Displacement / Capacity | 402 cc / 24.53 cu in |
| Bore X Stroke | 80.0 x 80.0 mm / 3.1 x 3.1 in |
| Compression Ratio | 6.7:1 |
| Cooling System | Air |
| Max Power | 31.4 kW / 43 hp @ 6500 rpm |
| Max Torque | — |
| Ignition | Suzuki PEI |
| Induction | Carburettor, Mikuni VM36SS |
| Start System | Kick |
| TRANSMISSION SPECS | |
| Lubrication | — |
| Gear Box | 5-speed |
| Clutch | Wet multiplate |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | High-tension steel pipe, single downtube, semi-double cradle |
| Front Suspension | Telescopic, coil spring, air/oil, infinitely adjustable damping; 249 mm / 9.8 in travel |
| Rear Suspension | Twin shocks (Tru-Trac), gas/oil damping, aluminium swingarm; 244 mm / 9.6 in travel |
| Front Brakes | Drum |
| Rear Brakes | Drum, full-floating |
| DIMENSION SPECS | |
| Overall Length | 2140 mm / 84.3 in |
| Overall Width | 885 mm / 34.8 in |
| Overall Height | 1225 mm / 48.2 in |
| Seat Height | — |
| Wheelbase | 1450 mm / 57.1 in |
| Ground Clearance | 290 mm / 11.4 in |
| Dry Weight | 105 kg / 231.5 lb |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | — |
| Rear Tyre | — |
| FUEL SYSTEM | |
| Fuel Capacity | 8.5 Litres / 2.25 US gal |
| Fuel Consumption | — |
| Top Speed | 148 km/h / 92 mph |
The 1978 big-bore two-stroke motocrosser (RM 400 C), an air-cooled 402 cc single with electronic ignition, a five-speed gearbox and Suzuki's twin-shock rear end with a full-floating drum brake. It was one of the largest open-class dirt bikes of its day.
