Next time you see a cyclist, take a look at their back wheel. If, like 95% of British bikes, it’s a rosette of cogs and gears, then the rider is, unfortunately, a Nineties throwback. If you see just a chain and a wheel, then they’re officially a Cool Person. Fixed-wheel bikes, loved by cycle messengers and trendies, are gradually sneaking into the mainstream.

Pre-history: Fixed-wheel bikes are as simple as a bike can be. You have to pedal constantly (there's no freewheeling, even downhill), but you don’t need brakes if you’re hardcore enough. They were traditionally used as track-racing bikes by sports riders, but in the late '90s they became a cult among cycle couriers in New York, San Francisco and London. In New York, there's always been a small fixed-wheel community around the Kissena Park velodrome in Queens.

The evangelist: Sheldon Brown is a mechanic from Massachusetts who has been passionately promoting fixed-wheel riding on his website since 1996. He talks about “the ineffable joy of the experience”.

Why bother? Aficionados say they love fixed-wheel bikes because they’re light, fast and cheap to maintain. They're also incredibly macho (Look Mum, no brakes!). It takes about three weeks to learn to ride a fixed-gear bike. You have to train your legs to pedal extra fast all the time, and then learn how to brake. You can also do stunts on a fixed-wheel bike , because the back wheel works like a unicycle. Think of it as skateboarding for people who actually need to get somewhere .

Going mainstream: Most of the big manufacturers now make fixed-wheel bikes, and they’re good value. 'Fixed' at the the Design Museum in London is a display of four old and new fixed-wheel bikes. In Japan, Nike have based an ad campaign around Fixie riders. There's even been a bit of press outrage about dangerous trendy brake-less riders .

Pictures from: Trilabracing and Levi Mpls

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