Yamaha SR250 (1978-79)

The Yamaha SR250 motorcycle was produced from 1978 to 1979 and had a four-stroke, single cylinder, SOHC, 2-valve engine with a capacity of 239cc. Its compression ratio was 8.9:1 and it had a 34mm Mikuni carburettor for fuel induction. The bike had a maximum power of 21hp at 7700 rpm and a maximum torque of 18.7 ft-lb at 7000 rpm. The transmission was five-speed and the final drive was a chain. The front suspension had 32mm telescopic forks and the rear suspension was dual shock with five-way preload adjustment. The brakes were drum, both front and rear. The front tire was 3.00-18 and the rear tire was 120/90-16. The wheelbase was 1340mm and the seat height was 740mm. The bike weighed 130kg and had a fuel capacity of 10.8 litres. Its average consumption was 70 mpg, and it could reach speeds up to 89 mph. The Yamaha SR250 was a reliable and efficient bike, with a moderate top speed and standing 1/4 mile time of 16.3 seconds.

Technical specifications:

Make Model: Yamaha SR 250

Year: 1978-79
Engine: Four stroke, single cylinder, SOHC, 2 valve
Capacity: 239 cc / 15.2 cu-in
Bore x Stroke: 73.5 x 56.5 mm
Cooling System: Air cooled
Compression Ratio: 8.9:1
Induction: 34mm Mikuni carburettor
Ignition: Electronically
Starting: Electric
Max Power: 21 hp / 15.7 kW @ 7700 rpm
Max Torque: 18.7 ft-lb / T25.5 Nm @ 7000 rpm
Transmission: 5 Speed
Final Drive: Chain
Front Suspension: 32mm Telescopic forks
Rear Suspension: Dual shock 5-way preload adjustment.
Front Brakes: Drum
Rear Brakes: Drum
Front Tyre: 3.00-18
Rear Tyre: 120/90-16
Wheelbase: 1340 mm / 52.75 in
Seat Height: 740 mm / 29.0 in
Wet Weight: 130 kg 287 lbs
Fuel Capacity: 10.8 Litres / 2.7 US gal
Consumption Average: 70 mpg
Standing 1/4 Mile: 16.3 sec
Top Speed: 89 mph / 143.2 km/h