Make Model: BSA Road Rocket
Year: 1954 – 58
Engine: Four stroke parallel twin cylinder, OHV
Capacity: 646 cc / 39.4 cub in.
Bore x Stroke: 70 x 84 mm
Cooling System: Air cooled
Compression Ratio: 7.2:1
Lubrication: Dry sump
Exhaust: Twin, stainless steel
Ignition: Lucas magdyno
Starting: Kick start
Max Power: 30 kW / 40 hp @ 6000 rpm
Clutch: Multi-plate with bult-in cush drive
Transmission: 4 Speed
Final Drive: Chain
Gear Ratio: 1st 11.68 / 2nd 7.96 / 3rd 5.48 / 4th 4.53:1
Frame: Welded seamless steel tubing with duplex downtubes and full cradle engine support, bolted-on rear sub frame
Front Suspension: Telescopic forks with coil spring – hydraulically damped
Rear Suspension: None or Plunger-type, with shock and rebound springs, undamped. From 1954: Swinging arm
Front Brakes: Drum, 8 in.
Rear Brakes: Drum, 7 in.
Wheels: Steel, wire spokes
Front Tyre: 3.25 x 19 in., ribbed
Rear Tyre: 4.00 x 19 in.
Dimensions: Length: 2100 mm / 84.0 in.
Wheelbase: 1391 mm / 54.75 in.
Dry Weight: 190 kg / 418 lbs
Fuel Capacity: 16 L / 4.2 US gal
Average Fuel Consumption: 5.6 L/100 km / 17.9 km/l / 42 US mpg
Top Speed: 175 km/h / 109 mph
Standing Quarter Mile (400 m): 16 sec.
Colours: All over gold, Black/chrome