Imagine you are an elite-level cyclist in a tight pack of competitors, seconds from the finish line. You feel you have the strength in your legs for one last push to win, but you need to shift up a gear to squeeze the last drop of power from your bicycle.

Slipping the bike’s complex mechanical gearing into a higher ratio, however, requires you to slow up for a fraction of a second and lose ground. Not only that, but the riders around you will hear the shift and may change gears themselves. Advantage lost.

But what if you were able to shift by touching a Bluetooth-equipped micro-switch, so that the action would be almost instantaneous and couldn’t be heard? A new, electronic gear hub in the center of the bike’s rear wheel makes such a “power shift” possible—and is becoming known among racers as the “silent assassin.”

The hub, developed by a Belgian-Dutch company, Classified, is already available from high-end cycle dealers in Europe and the U.S. and has even helped riders in the punishing off-road cycle sport of gravel racing. Classified is set to release a version for e-bikes and motor-assisted cycles, too.

Classified, a new, electronic gear hub in the center of the bike’s rear wheel, makes shifting instantaneous and silent.

Nick Evans, of Active Partners, the London growth investor who has put some $10 million into Classified, believes this almost literal re-invention of the wheel, a miniaturized version of Formula 1 race-car gearbox technology, will become the Intel of cycling. Meaning that, like the ubiquitous chips in computing, it will trickle down from rarefied bikes into everyday consumer cycles.

A full Classified kit, including the hub, a wheel, and wireless controls, starts at $1,500 in the U.S.

“It is a complete game changer,” says Nick Evans, who met with AIR MAIL in a fifth-generation family cycle store called Pearson Cycles in affluent Richmond, West London, where owner Will Pearson reports that keen hobby cyclists are snapping up the gadget.

“When people already spend hundreds on a saddle, a cost in the thousands for technology this revolutionary is acceptable to many of our customers,” says Pearson.

Classified has a growing bunch of former pro cyclists to back it, including the Belgians Tom Boonen and Philippe Gilbert.

In past decades, when we envisioned self-driving cars, hoverboards, and other exotic concepts as the likely personal transportation of the 21st century, it would have taken a brave futurologist to predict that the humble bicycle would be the preferred transport for smart young people in the 2020s—or that savvy investors such as Evans would be putting millions into refining the bike.

A combination of new factors—concern for the environment, interest in fitness, and the gumming up of cities by conventional traffic—has made cycling a booming market. And electronic bikes, which still require considerable effort by the rider but make for faster speeds and easier hill climbs, have further broadened the activity’s appeal.

Though e-bikes are more expensive than regular machines, there’s a growing interest in affordable converter kits to turn manual cycles into electric ones. Both the most successful and the most innovative of these kits come out of London start-ups.

Oliver Montague and Dmitro Khroma, the engineers behind Swytch Bike, started by raising money on crowd-funding platforms.

Still a niche product for enthusiasts, the Swytch Bike, which has been selling globally in ever lighter and more compact versions since 2017, requires a new, motorized front wheel and can be user-fitted to most (although not all) regular cycles. It typically sells for around $500 if you are prepared to wait a few weeks for your customized wheel to be built in the U.K.

Developed by a team in their 20s and 30s in East London, Swytch has sold some 60,000 kits to date and reports 27,000 in-progress orders on its books, according to the company. The company doesn’t have traditional investors and started out on crowd-funding platforms. As 33-year-old founder Oliver Montague says, “Our customers are our investors. We think that’s the most natural, organic way to grow, and it’s serving us well.”

The Swytch e-bike conversion kit requires a new, motorized front wheel that can be user-fitted to most regular cycles.

The approach is clearly working—ask about conversion kits in cycle stores and you find that Swytch is almost one of those brand names that has become generic.

Not yet so across town in North London, where perhaps the most innovative conversion gadget, named Skarper, is still in development for global launch in 2024.

Skarper is a detachable motor for a regular bike. AIR MAIL has seen it clicked into place on the rear wheel and then detached in a matter of seconds. The concept is that you might commute on a modest-looking bike—which wouldn’t be of interest to thieves—and take your valuable motor, weighing just a few pounds, into the office with you.

Skarper is very much an investment-supported company, having raised $10 million to date, much coming from champions of biking such as Sir Chris Hoy, the British cyclist with six Olympic gold medals to his name, and Ray Kelvin, founder of the Ted Baker fashion brand.

AIR MAIL rode with Hoy and found a Skarper-equipped bike to be exactly like a regular e-bike, with the feeling of a helping hand just when you need it.

Skarper has raised $10 million to date, much coming from champions of biking such as Sir Chris Hoy.

“It was an absolute eureka moment when I saw this,” Hoy says as we cycle. “I’d ridden e-bikes before, but this was something for the person who wants a regular bike and an e-bike in one. It’s a really neat solution that works on 90 percent of regular bikes.”

The team behind Skarper is very different from Swytch Bike’s knot of bike-mad engineers. Skarper was designed by a medical doctor and part-time inventor, Dr. Alastair Darwood, who is now in business with a South African lawyer, Ean Brown, and an Israeli military-helicopter pilot turned M.B.A, Uri Meirovich.

One possible drawback is the product name, which is Cockney slang for “to run away,” normally from the scene of a crime. Another is that Skarper has yet to sell a unit. The U.K. price will be roughly $1,200, and the U.S. price is still to be determined.

One possible drawback to Skarper is the product name, which is Cockney slang for “to run away,” normally from the scene of a crime.

The two high-profile cycle-gadget start-ups are no great friends, disagreeing as they do about whether rear-wheel motors (Skarper) or front-wheel (Swytch) are best. To be fair, Swytch’s Montague says either is fine, but he doubts that many people will want a detachable motor.

Amusingly, for connoisseurs of (characteristically male) attrition between competing hobbyist factions, each start-up accuses the other of recycling a Victorian-era idea.

Which cycling innovation the wheel of fortune will favor remains to be seen.

Based in London and New York, AIR MAIL’s tech columnist, Jonathan Margolis, spent more than two decades as a technology writer for the Financial Times. He is also the author of A Brief History of Tomorrow, a book on the history of futurology