The Yamaha XS 400 was a motorcycle produced in 1977-78. It had a four-stroke 180-degree parallel twin engine with a capacity of 392 cc and was air-cooled. The bike had two valves per cylinder and a compression ratio of 9.2:1. The XS 400 had a pressure-lubricated wet sump lubrication system, 2x Mikuni BS32 carburetors for induction, and electric and kick starting options. The bike had a maximum power output of 36 hp at 8100 rpm and maximum torque of 3.3 kgf-m at 8000 rpm. It had a wet multi-plate clutch and a 6-speed transmission, and its final drive was through a chain. The XS 400’s frame was made of tubular steel and was a semi-double cradle. It used a telescopic fork for front suspension and dual shocks swing arm for rear suspension. Its front brake was a single disc, and rear brake was a drum. The bike’s wheelbase was 1364 mm and its seat height was 780 mm. The XS 400 weighed 182 kg and had a fuel capacity of 14 litres.
Technical specifications:
Make Model: Yamaha XS 400
| Year | 1977 – 78 |
|---|---|
| Engine | Four stroke, 180 degrees parallel twin, SOHC, 2 valves per cylinder |
| Capacity | 392 cc / 23.9 cu-in |
| Bore x Stroke | 69.0 x 52.4 mm |
| Cooling System | Air cooled |
| Compression Ratio | 9.2:1 |
| Lubrication | Pressure-lubricated wet sump |
| Induction | 2x Mikuni BS32 carburetors |
| Ignition | Battery ignition – With contact breaker points |
| Starting | Electric & kick |
| Max Power | 36 hp / 26.8 kW @ 8100 rpm |
| Max Torque | 3.3 kgf-m / 23.8 lb-ft @ 8000 rpm |
| Clutch | Wet multiplate |
| Transmission | 6 Speed |
| Final Drive | Chain |
| Frame | Tubular steel, semi-double cradle |
| Front Suspension | Telescopic fork |
| Rear Suspension | Dual shocks swing arm, preload adjustable |
| Front Brakes | Single disc |
| Rear Brakes | Drum |
| Front Tyre | 3.00-18 |
| Rear Tyre | 3.50-18 |
| Wheelbase | 1364 mm / 53.7 in |
| Seat Height | 780 mm / 30.7 in |
| Wet Weight | 182 kg / 401 lbs |
| Fuel Capacity | 14 Litres / 3.7 US gal |
