Fixed-Gear Bicycle

In Australia, "fixed-wheel" is the normal term for the subject of this article — meaning the opposite of freewheel, and "fixed-gear" usually refers to a single-speed bicycle.

A fixed-gear bicycle (or fixed-wheel bicycle, sometimes known as a fixie) is a bicycle that has no freewheel, meaning it cannot coast, as the pedals are always in motion when the bicycle is moving.

The sprocket, or cog, is threaded or bolted directly to a fixed rear hub. When the rear wheel turns, the pedals turn in the same direction. This allows a cyclist to stop without using a brake by resisting the rotation of the cranks, and also to ride in reverse.

Uses

The track bicycle is a form of fixed-gear bicycle used for track cycling in a velodrome. But since a "fixed-gear bicycle" is just a bicycle without a freewheel, a fixed-gear bicycle can be almost any type of bicycle.

Some road racing and club cyclists used a fixed-gear bicycle for training during the winter months, generally using a relatively low gear ratio, believed to help develop a good pedalling style. In the UK until the 1950s it was common for riders to use fixed-gear bicycles for time trials. The 1959 British 25 mile time trial championship was won by Alf Engers with a competition record of 55 minutes 11 seconds, riding an 84 inch fixed-gear bicycle. The fixed-gear was also commonly used, and continues to be used in the end of season hill climb races in the autumn. A typical club men's fixed-gear machine would have been a "road/path" or "road/track" cycle. In the era when most riders only had one cycle, the same bike when stripped down and fitted with racing wheels was used for road time trials and track racing, and when fitted with mudguards (fenders) and a bag, it was used for club runs, touring and winter training. By the 1960s, multi-gear derailleurs had become the norm and riding fixed-gear on the road declined over the next few decades. Recent years have seen renewed interest and increased popularity of fixed-gear cycling.

In urban North America fixed-gear bicycles have achieved tremendous popularity, with the rise of discernible regional aesthetic preferences for finish and design details.

Dedicated fixed-gear road bicycles are being produced in greater numbers by established bicycle manufacturers. They are generally low in price and characterized by relaxed road geometry, as opposed to the steep geometry of track bicycles.

Fixed-gear bicycles are also used in cycle ball, bike polo and artictic cycling.

A fixed-gear bicycle is particularly well suited for track stands, a manoeuvre in which the bicycle can be held stationary, balanced upright with the rider's feet on the pedals.

Brakeless

Some fixed-gear riders think brakes are not strictly necessary, and brakeless fixed riding has a cult status in some areas. Brakes and their cables are said to add extra bulk to the simple appearance of a fixed gear bicycle.

Other riders dismiss riding on roads without brakes as an affectation, based on image rather than practicality. Riding brakeless can be dangerous, is prohibited by law in many jurisdictions, and may jeopardize the chances of a successful claim in the event of an accident.

Technique

It is possible to slow down or stop a fixed-gear bike by resisting the turning cranks, and a rider can also lock the rear wheel and skid to slow down or stop on a fixed-gear bicycle. Such a move is initiated by unweighting the rear wheel while in motion by shifting the rider's weight slightly forward and pulling up on the pedals using clipless pedals or toe clips and straps. The rider then stops turning the cranks, thus stopping the drivetrain and rear wheel, while applying body weight in opposition to the rotation of the cranks. This causes the rear wheel to skid, and slow the bike. The skid can be held until the bicycle stops or until the rider desires to continue pedalling again at a slower speed. The technique requires a little practice and using it while cornering is generally considered dangerous. A wet surface further reduces the effectiveness of this method.

On any bike with only rear wheel braking, the maximum deceleration is significantly lower than on a bike equipped with a front brake. As a vehicle brakes, weight is transferred towards the front wheel and away from the rear wheel, decreasing the amount of grip the rear wheel has. Transferring the rider's weight back increases rear wheel braking efficiency, but a front wheel fitted with an ordinary brake might provide 70% or more of the braking power when braking hard (see Weight transfer).

For more information, just click: en.wikipedia.org/wiki/Fixie