Sinclair C5 computers like the hugely successful ZX81 and ZX Spectrum, an affordable electric vehicle could unleash pent-up demand for a market that did not previously exist. However, Sinclair performed no market research to ascertain whether there was actually a market for his electric vehicle; as the director of the Primary Contact advertising agency commented in January 1985, the project continued all the way to the prototype stage "purely on the convictions of Sir Clive". With Sinclair's new specifications in hand, Ogle worked on a three-wheeled design dubbed the C5, which bore similarities with the earlier three-wheeled Bond Bug – another Ogle
Clive Sinclair kit, the MK14, based on the National SC/MP chip. By July 1978, a personal computer project was under way. When Sinclair learned the NewBrain could not be sold at below £100 as he envisaged, he turned to a simpler computer. In May 1979 Jim Westwood started the ZX80 project at Science of Cambridge; it was launched in February 1980 at £79.95 in kit form and £99.95 ready-built. In November, Science of Cambridge was renamed Sinclair Computers Ltd. In March 1981, Sinclair Computers was renamed again as Sinclair Research Ltd and the Sinclair ZX81 was launched at £49.95 in kit form