Ariel Four-Cylinder Prototype (1962)

The Ariel Four-Cylinder Prototype motorcycle, also known as the Ariel Leader 4 Prototype, was designed in 1962 but never went into full production. Its engine featured four horizontal cylinders on the left with an inline crankshaft and overhead valves, and it had a capacity of 696 cc. The bike was air-cooled and used a wet sump lubrication system, with a single Zenith carburetor for induction and an electric starter. The Ariel Four-Cylinder Prototype had a maximum power of 18.6 kW or 25 hp and used a Morris Minor car clutch with a syncro-mesh gearbox. The motorcycle had a four-speed transmission and used a shaft for final drive. Its frame was made of pressed steel and had leg shields, and it had steel wheels with laced wire spokes. The front and rear brakes were both drums. The Ariel Four-Cylinder Prototype had a wheelbase of 1448 mm or 57 inches. While this bike never reached full production, it remains an interesting prototype in motorcycle history. The information on this bike comes from the National Motorcycle Museum in the UK.

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Technical specifications:

Make Model: Ariel Leader 4 Prototype

Year: 1962

Production: Never reached full production

Engine: Four stroke, four horisontal cylinders on the left with in-line crankshaft, OHV

Capacity: 696 cc / 42.5 cu in

Cooling System: Air cooled

Lubrication: Wet sump

Exhaust: 4-into-1

Induction: Single Zenith carburetor

Ignition: Coil

Starting: Electric

Max Power: 18.6 kW / 25 hp

Clutch: Morris Minor car clutch, syncro-mesh gearbox

Transmission: 4-Speed

Final Drive: Shaft

Frame: Pressed steel frame with leg shields

Wheels: Steel, laced wire spokes

Front Rim: 3.25 x 17

Rear Rim: 4.00 x 16

Front Brakes: Drum

Rear Brakes: Drum

Wheelbase: 1448 mm / 57 in

Source: National Motorcycle Museum, UK