Many people who ride fixed-gear bicycles simply find it more enjoyable than or as an alternative to riding bikes with freewheels. Although the rider cannot change to a lower gear, climbing hills on a fixed gear is claimed by some riders to be easier than with a multi-speed freewheel; some claim it is because it is easier to maintain momentum as the cranks are pushed through the dead centres by the chain, other riders say it is only because a fixed bicycle is lighter than its multi-speed freewheel equivalent. In slippery conditions some riders prefer to ride fixed because the transmission gives feedback on back tire grip.
Descending is more difficult as the rider must spin the cranks at a very high speed, or use the brake(s) to slow down. Most riders are capable of pedaling at 150rpm, but some "fixed" experience is needed to pedal at 200rpm. Nevertheless, the enforced fast spin when descending is claimed to increase "souplesse" (a French word roughly meaning suppleness), which improves pedaling performance on any type of bicycle.
The fact that there is only one gear ratio (fixed not freewheel) can be an advantage or disadvantage depending on the rider. For a rider seeking to ride as fast or as far as possible for a given effort on varied terrain, it is a disadvantage.
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Furthermore, riding brakeless may jeopardize the chances of a successful insurance claim in the event of an accident. It also greatly increases stress on the knees which can lead to injury. Some will have one (usually front) brake for emergencies, for descending steep hills, for safety in the event of a broken or derailed chain, to comply with traffic law, or to prevent knee injury. UK law requires cycles to have two separate brakes, and the fixed wheel counts as one brake. Others will have two brakes for better control in hills, for slippery road conditions, or for use in the event of a broken or thrown chain, broken brake or brake cable.
In the United States, fixed-gear bikes without brakes are illegal in many places. Laws in most states where fixed-gear riding is popular -- including New York, California, Maryland, Oregon and Georgia -- require that bicycles be equipped with a brake that enables the operator to make the braked wheels skid on clean, dry pavement. Still, fixed-gear cyclists and lawyers in those states argue that the rider should count as the "brake" if the rider is able to achieve the same effect. In regulatory terms, the bikes fall in a gray area. The U.S. Consumer Product Safety Commission says track bicycles are "designed and intended for use in a competition." They are exempt from federal requirements for standard bicycles, which call for bikes to have brakes at least in the rear. Fixed-gear sidewalk bikes -- the commission's term for one with a seat height of no more than 25 inches adjusted to its highest position, and no free wheel -- aren't required to have brakes if they bear a permanent label visible from 10 feet displaying the words "No Brakes." The same label must be displayed prominently on promotional display material and shipping cartons.
