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How Bicycle Rollers Work


Operating Bicycle Rollers

Bicycle rollers operate simply. The cyclists climb into the saddle, their feet pump the pedals, the pedals turn the rear wheel, the rear wheel spins the rear rollers and the rear rollers drive the band that in turn spins the front roller. Nothing holds the rider atop the rollers except the force exerted by the wheels against the rollers.

While some prodigies of rollerdom can ride without using the handlebars or even remove their jackets over their heads without missing a pedal stroke, the task requires just one thing from neophytes: Pedal without falling over. Because there is no momentum in pedaling on rollers and riders have only the width of the drum to correct any imbalance before falling, this easy adage can be difficult in reality.

Before climbing on to the roller, the rider should secure the front axle just ahead of the front bicycle wheel to prevent it from driving off the roller. Except for very tall riders, most cyclists use a milk crate, a chair or some sort of makeshift step to climb onto the saddle. Many beginners place their bicycles inside a doorframe so they can reach out and support themselves as they mount and dismount their vehicle. A doorframe is also a way for cyclists to brace themselves if they lose their balance -- a very real hazard since nearly all cyclists ride on rollers with bikes that require clipping into the pedals. If a doorframe is unavailable, riding next to a wall and trying to fall only to that side is a suitable alternative. Regardless, pedaling on rollers next to a large glass coffee table is just an all-around bad idea.

Non-roller riders have a persistent fear that if they pedal off the rollers, a head-on collision with the nearest wall is in their immediate future. In reality, all of the energy a cyclist produces remains in the drums -- if the bike comes off the device, the wheels come to a halt. "The only way you can be propelled forward is if you keep pedaling, which I've never seen anyone do," Fry says. [source: Fry]

Even great road cyclists have a hard time on rollers. Turn the page to find out why.