Sir Clive back in the saddle

It is generally assumed that the current enthusiasm for cycling has as much to do with concern about health and fitness as the environment. But Sir Clive Sinclair, famed British inventor of calculators, digital watches and much else besides, reckons he has spotted a gap in the market for people who like to cycle without breaking sweat.

Sir Clive has been this way before, of course. In the early 1990s, after a spell operating mainly in computing and communications, he returned to the consumer market with the Zike electric bike and followed that with the 1994 launch of the Zeta. Essentially a kit for converting a conventional cycle into one equipped with a motorised boost for the tougher parts of a ride, it recovered from an inauspicious launch that saw the modified bike career out of control and went on to sell 15,000 around the world. It was withdrawn from production earlier this year ahead of the introduction of a more refined model.

The Zeta II (Zeta stands for Zero Emission Transport Accessory) is - as Sir Clive and the engineer chiefly responsible for it stress - much more stylish than its predecessor. It is also lighter in weight and, through breaking the pounds 100 barrier, on the pocket. The other key difference is that instead of being mounted on the rear wheel, it sits on the front. This both makes it easier to use and allows parcel racks or panniers to still be used at the back. The battery powering it is attached to the crossbar of a standard men's cycle or can be fitted between the tubes on women's or portable versions.

Sir Clive, who has also re-entered the consumer electronics market with what is believed to be the world's smallest radio, claims that the original Zeta was well-received, particularly among the middle-aged and over. But extensive feedback had led his company to set about producing a dramatic improvement, he said at last week's launch. "We've learned a lot and I think this is a real cracker of a product," he added.

With a market among older people already identified, Sir Clive and his team are confident that they can appeal to young people as well. "It is about putting the fun back into cycling and providing a viable, convenient alternative for the many thousands of short car journeys carried out each day," he said.

The company, which is running a national advertising campaign, hopes to sell about 1,000 units a month by the end of the year. But the Strathclyde factory operated by Trilec Sales & Manufacturing has the capacity to increase production significantly if there is a sudden demand.

The initial plan is to sell only via mail order in Britain and then to move into the export markets - particularly the Netherlands and the United States - where the first Zeta proved popular. Other electric bikes are currently available - though not in Britain and they are much more expensive. Since the Zeta II can be attached to just about any model of cycle, it enables a customer to obtain an electric bike for as little as pounds 200, while purpose-built models cost about pounds 500, says Sir Clive. It is reckoned that the kit can be fitted with the aid of a cycle spanner and screwdriver in about 20 minutes.

The motor - essentially the same as that used in power drills - limits the rider to a speed of 15 miles per hour, because that is the level below which anybody aged over 14 can use a powered machine without a licence, tax, insurance or helmet. It is activated by pulling a lever that drops a belt-and-pulley system patented by Sinclair Research on to the front tyre and then switching on the engine. Also among the innovations that the chief design engineer, Alex Kalogroulis, has introduced are fans to keep the motor cool.

Pointing out that the power boost enabled a reasonably fit cyclist to tackle some of Britain's steepest hills with relative ease, Mr Kalogroulis said: "I think the reason more people do not cycle to work is that they arrive hot and sweaty and need a shower. I think we have cracked that."

The 12-volt battery, which can be recharged about 500 times at about a penny each time, will power a typical cyclist at speeds of up to 12.5 miles per hour for about five miles. This life can be extended to 10 to 15 miles, if the user pedals at the same time as engaging the motor.

Although Sinclair Research's extensive surveys indicate that this is beyond most people's trip range, Mr Kalogroulis emphasised that it was possible to carry two batteries on the cycle and switch over the power leads when required. Alternatively, a cyclist could have one battery and recharger at work and another at home.

q Further details: Vector Services (on behalf of Sinclair Research), Northampton. Tel: 01933 279300.