Yamaha XJ550 Seca (1981)

The Yamaha XJ550 Seca is a four-stroke, transverse four-cylinder motorcycle that was produced in 1981. It has 528cc and 2 valves per cylinder with a compression ratio of 9.5:1. It uses 4x 28mm Mikuni carburetors and has battery-powered inductive ignition. The bike can produce a max power of 37 kW / 50 PS at 9000 rpm and a max torque of 41.9 Nm / 4,3 m-kg at 7500 rpm. It features a 6-speed transmission and a chain final drive. The bike has telescopic coil spring forks in the front and a swinging arm with dual dampers that are adjustable for preload in the rear. The front brakes are dual 267mm discs while the rear brake is a 182mm drum. The bike weighs 205 kg / 450 lbs and has a fuel capacity of 15 liters / 3.9 US gal. It has an average fuel consumption of 55 mpg, can do a standing 1/4 mile in 13.4 seconds at 98 mph and has a top speed of 178.6 km/h / 111 mph.

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Technical specifications:

Make Model: Yamaha XJ 550R Sega

Year: 1981

Engine: Four stroke, transverse four cylinder. DOHC, 2 valves per cylinder.

Capacity: 528 cc / 32.2 cu-in

Bore x Stroke: 57 X 51.8 mm

Cooling System: Air cooled

Compression Ratio: 9.5:1

Induction: 4x 28mm Mikuni carburetors

Ignition: Battery powered inductive

Starting: Electric

Max Power: 37 kW / 50 PS @ 9000 rpm

Max Torque: 41.9 Nm / 4,3 m-kg @ 7500 rpm

Transmission: 6 Speed

Final Drive: Chain

Front Suspension: Telescopic coil spring forks

Front Wheel Travel: 137 mm / 5.3 in

Rear Suspension: Swinging arm with dual dampers adjustable for preload

Rear Wheel Travel: 80 mm / 3.7 in

Front Brakes: 2x 267mm discs

Rear Brakes: 182mm Drum

Front Tyre: 3.25-19

Rear Tyre: 110/ 90-16

Wet Weight: 205 kg / 450 lbs

Fuel Capacity: 15 liters / 3.9 US gal

Consumption Average: 55 mpg

Standing 1/4 Mile: 13.4 sec / 98 mph

Top Speed: 178.6 km/h / 111 mph