ABC 8 hp

The ABC 8 hp is an 8 hp (6 kW) two-cylinder aero engine designed by British engineer Granville Bradshaw for use in ultralight aircraft. The engine was derived from a specially tuned motorcycle unit and was built by ABC Motors, first running in 1923.
The ABC 8 hp was used in the English Electric Wren and Handley Page H.P.22. In theEnglish Electric Wren, with barely enough power to maintain flight, the aircraft is assisted into the air by a team of volunteers using bungee cord, after which the Wren lands straight ahead following a short 'hop'.

Components:
Valvetrain: Overhead valve, two valves per cylinder
Fuel system: Carburettor
Fuel type: Petrol
Cooling system: Air-cooled

Type: 2-cylinder air-cooled flat-twin
Bore: 2.72 in (69 mm)
Stroke: 2.13 in (54 mm)
Displacement: 24.76 cu in (404 cc)
Dry weight: 41 lb (18.6 kg)
Power output: 8 hp (6 kW) at 4,500 rpm
Power-to-weight ratio: 0.2 hp/lb (0.32 kW/kg)