Objectively it is the merest pimple of a mountain, but for cyclists in London and south-east England, Box Hill in Surrey looms large. I had climbed it hundreds of times, so often that every subtle change in gradient, every pothole, drain and blemish in the tarmac was agonisingly familiar. But this time something was very different. I was overtaking Graham, my longtime cycling partner and rival, then leaving him far behind. I was flying up the hill, having to lean the bike right over so as not to overshoot the corners. I felt like Lance Armstrong or Marco Pantani.

Which is to say, I felt like a great climber but also something of a fraud. They both used performance-enhancing drugs; I was benefiting from a new type of cheating, something that has become known in the professional cycling world as “mechanical doping” — the use of small but powerful electric motors, entirely concealed from view.

Allegations of their use in professional cycling first emerged in 2010, when an online video featuring Italian former professional cyclist Davide Cassani became a viral sensation. It appeared to show a bike whose pedals turned on their own, and went on to suggest that the Swiss cyclist Fabian Cancellara might have used a motor to speed away from the peloton before winning that year’s Paris-Roubaix race.

The 2010 video that raised the issue of “mechanical doping” in cycling

Most cyclists dismissed the video as a paranoid conspiracy theory. “It’s so stupid, I’m speechless,” said Cancellara (whose innocence was confirmed by the sports authorities). And while the rumours and insinuations about mechanical doping have continued to circulate — one television commentator during last summer’s Tour de France said Chris Froome’s bike “seemed to be pedalling itself” — many fans still treat the whole idea as a bit of a joke. When Brian Cookson, president of the sport’s governing body, revealed that it was testing bikes for hidden motors during the Tour de France, he sounded almost embarrassed: “Although this subject sometimes causes amusement and derision, we know that the technology is available.”

That tiny, high-tech, hidden motors could be available to amateur riders seems even more far-fetched — none of the keen cyclists I spoke to in London knew anything about them. So arriving at Box Hill, on a recent overcast morning, I was dubious.

The bike I had come to try is the first concealed-motor racing bike from a UK manufacturer. Built by Somerset-based Electric Mountain Bikes, it will be launched this month under the company’s new brand, Goat Bikes, and will sell for £4,049. With a magnesium alloy frame, carbon fork and Shimano Ultegra gears, it looks just like any other mid-range racing bike. The slim, cylindrical motor is concealed in the lower part of the seat tube (the vertical piece of the frame which runs down from saddle to the bottom bracket) and connects with the crank axle.

While early electric bikes had heavy, cumbersome lead-acid batteries, the use of lithium means the battery can be hidden within what looks like a conventional water bottle. A tiny black rubber switch, on the end of the drop handlebars, turns the power on; stop pedalling and it turns off. Tutorial over, I set off to test it, on multiple ascents of the hill.

The motor and battery are hidden in the frame and bottle © Tom Jamieson

First impressions were of a very gentle boost (in time-honoured fashion, Graham still thrashed me to the top). But then Steve Punchard, founder of Electric Mountain Bikes, adjusted the motor to increase the cadence and everything changed.

There was a marked boost in speed but, perhaps more importantly, the power felt completely natural. It was not like sitting on a moped just watching the scenery pass (what would be the point?). You still need to pedal, your heart rate is still raised; it still feels like you are engaged in an active, physical sport. Unlike conventional electric bikes, whose large batteries can give a powerful boost for several hours, the concealed one lasts for just an hour, making it suitable for getting over the toughest summit on a ride, or helping an exhausted rider over the final few miles. The motor and battery add about 1.8kg to the weight of the bike, but its handling remains unchanged.

As I dropped Graham and accelerated up the hill, my mind began racing with the implications of the modest-looking machine beneath me. Ageing riders will be able to keep going later in life; cycle holidays touring the great Alpine passes will no longer be restricted to the super-fit; couples of differing abilities will be able to ride together. Nervous novices will be able to join club rides without fear of holding others back, and on bikes that look like any other and don’t mark them out as rookies.

“It is democratising access to the biking experience,” says Norman Howe, chief executive of Butterfield & Robinson, which already offers electric bikes on its worldwide bike tours, though not yet with concealed motors. “There’s that ego-anxiety around this stuff — of not wanting to admit you need the help — but the more discreet the systems get, the less that issue plays out.”

The Goat bike © Tom Jamieson

Equally clear, as I whipped past other riders on expensive-looking bikes, is that there will be controversy. Much amateur riding and cycle travel is geared towards timed, mass-participation events known as sportives or gran fondos. Officially they are just for fun, but many riders take their time and their final ranking extremely seriously, training all year to better their results.

“You’d be very naive to think that people aren’t going to use them in sportives,” says Michael Hutchinson, a former international racer and author of Faster: The Obsession, Science and Luck Behind the World’s Fastest Cyclists. “At this point the technology isn’t that readily available, but when that changes, someone will argue, ‘Oh, well it will help me with my training, I’ll get to work faster’. Then it becomes a much smaller step to be in a sportive and think, ‘Well I’ll just use it up this bit here . . . ”

I felt like Lance Armstrong or Marco Pantani, which is to say, a great climber but also something of a fraud

In fact, though no mainstream bike manufacturer sells such bikes and the concept remains little-known in the English-speaking world, the motors and batteries, manufactured by an Austrian company called Vivax, can already be bought through numerous dealers in Germany, Austria and the Netherlands. In those countries, where cycling has traditionally been a means of everyday transport as well as a sport, electric bikes are far more common. “But I think British people still tend to regard them as just not quite cricket,” says Hutchinson.

Though the invisibility of the Goat bike’s system will remove any stigma, one giveaway remains — a distinct whirring noise when the motor is switched on. Future versions are likely to be quieter, but even the current system could be used while alone on a long climb, or to catch up if dropped by the peloton. “There are always going to be some people who are keen to cut corners,” says Ian Holt, founder of specialist tour operator La Fuga, which takes hundreds of cyclists to ride in European sportives each year. “People will be super-suspicious of each other.”

As I turned the final corner on Box Hill, I checked my time. At the peak of my cycling enthusiasm, I would climb Box Hill in seven minutes. Then, two years ago, a baby arrived and my weekly training mileage abruptly dropped from 200 to precisely zero. But here I was, arriving at the hilltop café with a new personal best of just over six minutes. In a world where many amateurs are happy to spend fortunes on the lightest carbon wheels or most aerodynamic frame, just to shave off a few seconds, that kind of performance enhancement might prove too hard to resist.

Details

The Goat Race bike costs £4,049. See electricmountainbikes.com and goatbikes.com; tel: 01458 550304

Photographs: Tom Jamieson