The Sinclair C5 was a battery electric vehicle invented by Sir Clive Sinclair and launched in the United Kingdom on 10 January 1985. The vehicle is a battery-assisted tricycle steered by a handlebar beneath the driver's knees. Powered operation is possible making it unnecessary for the driver to pedal. Its top speed of 15 miles per hour (24 km/h), is the fastest allowed in the UK without a driving licence. It sold for £399 plus £29 for delivery. It became an object of media and popular ridicule during 1980s Britain and was a commercial disaster, selling only around 12,000 units.

The C5's lack of seat-to-pedal adjustment, lack of gears, short pedal cranks, and that the motor overheated on long hills were serious problems; indeed the motor was essentially useless for climbing hills, with even mild gradients necessitating significant pedal assistance, which rendered the vehicle largely pointless.