| MODEL | YAMAHA SRX 400 1985 - 1986 |
| Year | 1985 - 1986 |
| Engine Type | Four stroke, single cylinder, SOHC, 4 valves |
| Displacement / Capacity | 399 cc / 24.3 cu in |
| Bore X Stroke | 87 x 67.2 mm |
| Compression Ratio | 9.2:1 |
| Cooling System | Air cooled |
| Max Power | 24.6 kW / 33 hp @ 7000 rpm |
| Max Torque | 3.4 kgf-m / 24.5 lb-ft @ 6000 rpm |
| Ignition | TCI |
| Induction | YDIS twin carburetor |
| Start System | Kick |
| TRANSMISSION SPECS | |
| Lubrication | — |
| Gear Box | 5 speed |
| Clutch | — |
| Final Drive | Chain, 428 heavy duty O-ring, 138 links |
| CHASSIS SPECS | |
| Frame | — |
| Front Suspension | Telescopic forks |
| Rear Suspension | Dual shocks |
| Front Brakes | Single 320 mm disc, 4 piston caliper |
| Rear Brakes | Single disc |
| DIMENSION SPECS | |
| Overall Length | — |
| Overall Width | — |
| Overall Height | — |
| Seat Height | — |
| Wheelbase | — |
| Ground Clearance | — |
| Dry Weight | 147 kg / 324 lb |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | 110/70-17 tubeless |
| Rear Tyre | 140/70-17 tubeless |
| FUEL SYSTEM | |
| Fuel Capacity | 15 Litres / 4.0 US gal |
| Fuel Consumption | — |
| Top Speed | — |
The SRX400 was the Japanese-market 400 cc version of Yamaha's sporty four-valve single, sized to suit domestic tax and licence limits. It combined an air-cooled SOHC engine with kick start, a slim alloy-trimmed chassis and low seat, and was widely imported as a grey-market machine. A retro-flavoured, nimble city and back-road bike, it sold modestly against four-cylinder rivals.
