Sinclair Research "FM Wristwatch Radio", an LCD wristwatch with a radio attached. However, the watch had several problems and never went into full production. Sinclair had long had an interest in electric vehicles, and during the early 1980s he worked on the design of a single-seater "personal vehicle", eventually starting a company called Sinclair Vehicles Ltd in March 1983. He launched the Sinclair C5 electric vehicle on 10 January 1985, but it was a commercial disaster, selling only 17,000 units and losing Sinclair £7,000,000. Sinclair Vehicles went into liquidation later the same year. The failure of the C5, combined with those of
Sinclair C5 until late 1979 that Sinclair returned to electric vehicle development. Around Christmas that year, he approached Tony Wood Rogers, an ex-Radionics employee, to carry out consultancy work on "a preliminary investigation into a personal electric vehicle". The brief was to assess the options for producing a one-person vehicle which would be a replacement for a moped and would have a maximum speed of . Although Wood Rogers was initially reluctant, he was intrigued by the idea of an electric vehicle and agreed to help Sinclair. The vehicle was dubbed the C1 (the C standing for Clive). He built a number