They are labelled by some cyclists as 'cheating' and lazy'. But that hasn't stopped electric bikes, or e-bikes, from becoming an increasingly popular choice for those who would prefer to get around on two wheels rather than four.
Last month a rise in sales of e-bikes was given as one of the reasons why national chain Halfords had turned its fortunes around.
Meanwhile, in Norwich, cycle shops have reported that their sales have soared.
Scott Cordy, owner of Pedal Addiction Cycles, on Bowthorpe Road, said it was the 'biggest growing side of the business'.
Philip Crowhurst, manager of Evans Cycles on Westlegate, said that sales of e-bikes have increased 179% compared to last year. While this is below the national average of 379%, it is still 'significant growth', with the majority of buyers classified as commuters.
Norwich man Loz Coward disagrees with the lazy tag. The 44-year-old, who bought an e-bike last year and rides it to and from work, has said they are 'not an alternative to cycling' but to other forms of commuting.
An e-bike, also known as a pedelec, is fitted with a small electric motor which assists a cyclist's pedal power.
Mr Coward works at ReAssure, a life and pensions company based at Aviva's offices on Surrey Street, and lives in Thorpe Hamlet - a commute of three miles.
Some years ago, he used to cycle to work. 'But a mixture of traffic and weather meant it wasn't comfortable to ride,' he said. 'Battling against the wind and rain in October, up a hill, was a nightmare.'
Mr Coward instead bought a motorbike which he rode until April last year, when he saw an e-bike in Halfords.
While riding the e-bike, which he uses more or less exclusively for commuting, Mr Coward still has to pedal, and riding up hills is still difficult. 'But on those horrible days I have the opportunity to push up the motor a bit more,' he said.
The bike's motor has five settings, from eco mode, which gives a small push, to turbo.
He described riding up Kett's Hill at 'eleven or twelve mph without having to put too much effort into it'.
Mr Coward now gets to work quicker than he ever has before. During hot weather, colleagues who ride regular bikes sometimes arrive to work covered in sweat. 'I don't,' Mr Coward said.
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