Sinclair gets on his bike again with latest invention

Sir Clive Sinclair is about to take to the roads again, two decades after his electric tricycle the C5 flopped so spectacularly.

The Cambridge inventor will usher in what he describes as a new era in personal transport next month when he unveils his latest product - the world's lightest portable bike.

Weighing in at just 12lbs and small enough to fold up inside a rucksack and stow on the luggage rack of a train, Sir Clive claims the A-Bike will revolutionise urban commuting.

The A-Bike is made of heat-treated aluminium, folds in three places and sports tiny buggy-sized wheels, which is not obviously suited to pot-holed urban streets. However, a spokesman insisted that the bike had been road-tested and would be suitable for UK roads.

Sinclair Research refused to disclose how many of the portable bikes it hopes to sell or how much they will cost, but it is understood the A-bike will sell for less than the world's most popular folding bike, the Brompton, which starts at £380.

The A-bike will be manufactured in Malaysia and its chief design engineer is Alex Kalogroulis.

This is not the first time that Sir Clive has experimented with a road vehicle since the ill-fated launch of the C5 in the mid-1980s. In 1992, he launched an electric-powered bike called the Zike, which was priced at £499.99 and modestly described as "the greatest invention since the bicycle".

Designed to re-charge itself going down hills and with a top speed of 10 mph, Sir Clive planned to produce 10,000 Zikes a month. In the event, production was stopped after six months with just 2,000 bikes having been sold. They are now a collector's item. Sir Clive will be hoping the same fate does not await the A-Bike.