The Yamaha XS 400 US. Custom motorcycle specifications include a 392 cc (23.92 cu in) engine, power of 27 hp (19.7 kW) @ 7,500 rpm, a 6-speed gearbox, and a listed weight of 180 kg (396.8 lb).
Key specifications
How the Yamaha XS 400 US. Custom compares
This compares the motorcycle with all Yamaha models in this specifications database. The blue marker is this model and the grey line is the Yamaha database average.
About 49% lower than the Yamaha database average. Around the 43rd percentile across Yamaha models.
About 29% lower than the Yamaha database average. Around the 45th percentile across Yamaha models.
Very close to the Yamaha database average. Around the 49th percentile across Yamaha models.
About 7% larger than the Yamaha database average. Around the 57th percentile across Yamaha models.
Yamaha database percentile rankings
Percentiles show where this motorcycle sits across the Yamaha specifications database. They are descriptive database rankings, not performance ratings.
27 hp — more powerful than about 43% of Yamaha models with power data.
392 cc — larger displacement than about 45% of Yamaha models.
180 kg — heavier than about 49% of Yamaha models, or lighter than about 51%.
14 L — larger than about 57% of Yamaha fuel tanks in this database.
Mechanical overview
Additional useful specifications
| Front tire size | 3.00-18 |
|---|---|
| Rear tire size | 120/90-16 |
| Rear tire width | 120 mm |
| Rear tire aspect ratio | 90% |
| Rear rim diameter | 16 in |
| Power-to-weight ratio | 0.150 hp/kg |
| Power-to-weight | 150.0 hp/tonne |
| Specific power | 68.9 hp/L |
| Bore/stroke ratio | 1.32:1 (Oversquare) |
Model information
| Year released | 1980 |
|---|---|
| Category | Classic |
Engine specifications
| Engine type | Twin, four-stroke |
|---|---|
| Displacement | 392 cc (23.92 cu in) |
| Power | 27 hp (19.7 kW) @ 7,500 rpm |
| Bore × stroke | 69.0 x 52.4 mm (2.7 x 2.1 inches) |
| Compression ratio | 9.3:1 |
| Valves per cylinder | 2 |
| Cooling system | Air |
| Fuel control | Overhead Cams (OHC) |
Transmission and drivetrain
| Gearbox | 6-speed |
|---|---|
| Final drive | Chain (final drive) |
Brakes, wheels and tires
| Front brakes | Single disc |
|---|---|
| Rear brakes | Expanding brake |
| Front tire | 3.00-18 |
| Rear tire | 120/90-16 |
Dimensions and weight
| Wet weight | 180 kg (396.8 lb) |
|---|
Fuel and emissions
| Fuel capacity | 14.00 L (3.70 US gal) |
|---|
Performance
| Top speed | 139.0 km/h (86.4 mph) |
|---|
Disclaimer: Specifications may vary by market, trim, production date and optional equipment, and scraped or historical data can contain errors. Comparison and percentile values are calculated from Yamaha models in this specifications database. Always double-check important specifications against the motorcycle owner’s/service manual and official Yamaha information before relying on them. Visit the official Yamaha website.