The Yamaha XS 400R Seca, manufactured in 1982, has a four-stroke parallel twin engine with a capacity of 399cc, a bore and stroke of 69.0 x 53.4mm, and a compression ratio of 9.7:1. The cooling system is air-cooled and the lubrication is wet sump. The bike has 2x 32mm Mikuni carburetors and a transistorized ignition with electric starting. It can produce a maximum power of 45.5 hp / 34 kW @ 9500 rpm and a maximum torque of 3.5 kgf-m / 25.3 lb-ft @ 8000 rpm.
The clutch is wet and multiplate, with a six-speed transmission and chain final drive. The pressed steel spine frame has the engine as a stressed member, and it has hydraulic telescopic forks at the front with a travel of 138mm / 5.5in, and a monocross system with a single coil-sprung, gas/oil damped shock at the rear with a travel of 96.5mm / 3.8in.
The front brakes have 2x discs and the rear brakes are drums. The front and rear tires have sizes 3.00-18 and 4.10-18 respectively. The rake is at 63 degrees and the trail at 95mm / 3.74in. The bike has a dry weight of 169kg / 372.9lbs and a fuel capacity of 18 liters / 4.7 US gal.
Technical specifications:
Make Model: Yamaha XS 400R Seca
| Year | 1982 – |
|---|---|
| Engine | Four stroke, parallel twin, DOHC, 2 valves per cylinder |
| Capacity | 399 cc / 24.3 cu-in |
| Bore x Stroke | 69.0 x 53.4 mm |
| Cooling System | Air cooled |
| Compression Ratio | 9.7:1 |
| Lubrication | Wet sump |
| Induction | 2x 32mm Mikuni carburetors |
| Ignition | Transistorized |
| Starting | Electric |
| Max Power | 45.5 hp / 34 kW @ 9500 rpm |
| Max Torque | 3.5 kgf-m / 25.3 lb-ft @ 8000 rpm |
| Clutch | Wet, multiplate |
| Transmission | 6 Speed |
| Final Drive | Chain |
| Frame | Pressed steel spine with engine as stressed member |
| Front Suspension | Hydraulic telescopic forks |
| Front Wheel Travel | 138 mm / 5.5 in |
| Rear Suspension | Monocross system with single coil sprung, gas/oil damped shock, pre-load adjustable |
| Rear Wheel Travel | 96.5 mm / 3.8 in |
| Front Brakes | 2x discs |
| Rear Brakes | Drum |
| Front Tyre | 3.00-18 |
| Rear Tyre | 4.10-18 |
| Rake | 63 degrees |
| Trail | 95 mm / 3.74 in |
| Dry Weight | 169 kg / 372.9 lbs |
| Fuel Capacity | 18 Litres / 4.7 US gal |
