|Body and chassis|
||250 W (0.34 hp)|
|Range||20 miles (32 km)|
||1,304 mm (51.3 in)|
|Length||1,744 mm (68.7 in)|
|Width||744 mm (29.3 in)|
|Height||795 mm (31.3 in)|
||30 kg (66 lb) without battery, approx. 45 kg (99 lb) with battery|
The Sinclair C5 is a small one-person
Sinclair had become one of the UK's best-known millionaires, and earned a
On 10 January 1985, the C5 was unveiled at a glitzy launch event but it received a less than enthusiastic reception from the British media. Its sales prospects were blighted by poor reviews and safety concerns expressed by consumer and motoring organisations. The vehicle's limitations – a short range, a maximum speed of only 15 miles per hour (24 km/h), a battery that ran down quickly and a lack of weatherproofing – made it impractical for most people's needs. It was marketed as an alternative to cars and bicycles, but ended up appealing to neither group of owners, and it was not available in shops until several months after its launch. Within three months of the launch, production had been slashed by 90%. Sales never picked up despite Sinclair's optimistic forecasts and production ceased entirely by August 1985. Out of 14,000 C5s made, only 5,000 were sold before its manufacturer,
The C5 became known as "one of the great marketing bombs of postwar British industry"  and a "notorious ... example of failure".  Despite its commercial failure, the C5 went on to become a cult item for collectors. Thousands of unsold C5s were purchased by investors and sold for hugely inflated prices – as much as £5,000, compared to the original retail value of £399. Enthusiasts have established owners' clubs and some have modified their vehicles substantially, adding monster wheels, jet engines, and high-powered electric motors to propel their C5s at speeds of up to 150 miles per hour (240 km/h).
The C5 is made predominately of polypropylene, measuring 174.4 cm (68.7 in) long, 74.4 cm (29.3 in) wide, and 79.5 cm (31.3 in) high. It weighs approximately 30 kg (66 lb) without a battery and 45 kg (99 lb) with one.  The chassis consists of a single Y-shaped steel component with a cross-section of about 5.5 cm (2.2 in) by 4 cm (1.6 in)  The vehicle has three wheels, one of 317 mm (12.5 in) diameter at the front and two of 406 mm (16.0 in) at the rear. 
The driver sits in a recumbent position in an open cockpit, steering via a handlebar that is located under the knees. A power switch and front and rear brake levers are positioned on the handlebar. As a supplement to or replacement for electric power, the C5 can also be propelled via bicycle-style pedals located at the front of the cockpit. The maximum speed of an unmodified C5 is 15 miles per hour (24 km/h). At the rear of the vehicle is a small luggage compartment with a capacity of 28 litres (1 cu ft).  As the C5 does not have a reverse gear, reversing direction is done by getting out, picking up the front end and turning it around by hand. 
The C5 is powered by a 12-volt lead-acid electric battery driving a motor with a continuous rating of 250 watts and a maximum speed of 4,100
Although it was usually billed as an electric vehicle, the C5 also depends significantly on pedal power. The vehicle's battery is designed to provide 35 amps for an hour when fully charged or half that for two hours, giving the C5 a claimed range of 20 miles (32 km).
 A display in the cockpit uses green, amber, and red
The C5 was initially sold at a cost of £399, but to keep the cost under the £400 mark a number of components were sold as optional accessories.  These included indicator lights, mirrors, mud flaps, a horn, and a "High-Vis Mast" consisting of a reflective strip on a pole, designed to make the C5 more visible in traffic. Sinclair's C5 accessories brochure noted that "the British climate isn't always ideal for wind-in-the-hair driving" and offered a range of waterproofs to keep C5 drivers dry in the vehicle's open cockpit. Other accessories included seat cushions and spare batteries.