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10 May 2017

Sinclair C5 at Thinktank

The 1980s produced some wonderful inventions such as the walk man, the first Mobile Phone and the Space Shuttle, but it also produced some that seemed destined for failure. One such unfortunate invention was Sir Clive Sinclair’s C5. Not only does it rank as one of the most spectacular transport failures of the 1980s, but it also has the dubious distinction of being named the worst gadget of all time, but was it really as bad as we all seem to think?

Sir Clive Sinclair was known for being at the forefront of British innovation for many years by the time he tried his hand at vehicles. He had invented pocket radios, pocket TVs, electronic watches and was one of the visionaries who made personal computing a reality. Launched in 1980, his ZX-80 PC helped usher in the PC age. At a price of just £100 the ZX-80 was a hit and the machine put Sinclair at the heart of the United Kingdom’s PC revolution. Ongoing development resulted in the ZX-Spectrum that sold 5 million units following its launch in 1982.

Sir Clive Sinclair meets young inventors in 1992. Picture Taken By Adrian Pingstone

Sir Clive Sinclair meets young inventors in Bristol (England) in 1992. (Image credit: Photo by Adrian Pingstone and released into the public domain. Image from wiki commons ).

Sinclair started to think about electric vehicles as a teenager, and it was an idea he toyed with for decades. In the early 1970s Sinclair Radionics was working on the project. Sinclair had Chris Curry work on the electric motor. However, the company focus shifted to calculators and no further work was done on vehicles until the late 1970s. Development began again in 1979 and progressed erratically until, in 1983, it became apparent that new legislation would alter the market and make it possible to sell a vehicle closely resembling development efforts. As time went on, the Sinclair research C5 development cost gradually increased. In March 1983, Sinclair sold some of his shares in Sinclair Research and raised £12 million to finance vehicle development. In May a new company, Sinclair Vehicles Ltd, was formed out of Sinclair Research and a development contract entered with Lotus to take the C5 design to production.

At the same time, the Hoover Company at Merthyr Tydfil contracted to manufacture the C5. This, together with the fact that the motors were made by Polymotor in Italy, started the urban myth that the C5 was powered by a washing machine motor. In 1984, Sinclair Vehicles set up head office at the University of Warwick Science Park. When built the C5 had a battery that could provide an 18.7-miles (30 kilometres) range, at up to 15mph (25km/h), and peddle assist for when going uphill. Steering was done with handlebars under the rider’s legs as they leaned back.

Driving a Sinclair C5 By Adam

Driving a Sinclair C5 By Adam (image credit: From Adam on Flickr , Creative Commons licence.)

The C5 had an almost instant image problem, as many saw it not as a new mode of transport and rather as a quite expensive toy, and its image problems only got worse. The cold weather shortened battery life, the driver was exposed to the weather, and because it was low to the ground, doubts were raised about the safety in traffic. The problems were addressed with a second battery, and the C5 did have a hi-tech “silicon chip control system” to monitor the battery charge and electric motor temperature, and to tell the driver when to add some pedal assistance. The trouble is, that turned out to be far too often. Side screens for bad weather and a reflector on tall poles were available as extras from the launch.

The C5 was meant to be merely the starting point in a whole family of electric vehicles. Sinclair envisaged producing follow-up vehicles such as the C10. It was intended to be a city car, capable of carrying two passengers at up to 40 miles per hour (64 km/h) in a roofed but open-sided compartment with two wheels at the front and one at the back. Sinclair built a full-scale mock-up of it; according to Wood Rogers (C5 designer and concept designer of the C10 and C15), "it looked great. I specified open sides to keep the cost down and having no doors meant it escaped a lot of regulations too."

Sinclair described his other electric vehicle concept the C15 as having "a futuristic design with an elongated 'tear-drop' shape, a lightweight body made of self-coloured polypropylene and a single, possibly 'roller' type rear wheel". It would have been launched at the 1988 International Motor Show in Birmingham following a development programme costed at £2 million. Unlike the relatively conventional technology used in the C5, Sinclair intended to use sodium sulphur batteries with four times the power-to-weight ratio of lead-acid batteries to give the C15 much greater speed and range – over 180 miles (290 km) on a single charge. It would have had approximately the same dimensions as a conventional small car. However, it could only have worked if sodium sulphur batteries had realised their promise. In the end this would not matter as neither the C10 nor the C15 ever left the drawing board.

The poor reception of the C5 meant that production ended about eight months after its launch. The C5 debacle did lasting damage to the reputation of subsequent to electric vehicles in the UK, which the media routinely compared to the C5. In the decades since, battery technology has improved, as have electronic control systems for safety and stability. The appetite for alternatives to petrol-engine cars is growing, with some electric vehicles becoming sales success stories. In 2017 Sir Clive's nephew Grant Sinclair presented what he called an updated version of the Sinclair C5 called the Iris eTrike. Perhaps if the C5 were to be introduced now, it would also be a success.