A fixed-gear bicycle, known also as fixed-wheel bicycle or fixie, is the simplest in terms of construction type of bicycle that has a drivetrain with no freewheel mechanism.
Name “fixed gear” may refer to the mechanism itself as well as to the whole bicycle based on it. The main rule of it is lack of freewheel and derailleurs – drivetrain has the drive sprocket bolted stiffly to the hub of back wheel. Fixies have only one gear and ride comes along with constant pedaling. Such solution used to be applied to children bikes, though it originates from technology used in track bikes. This type tends to get more and more popular among bikers who need to move smoothly around crowded streets in the city.
Advantages of a fixed gear
The fixed gear has a reputation for reliability. This is due to the simplicity of construction – the simplest accessories, no derailleurs and unnecessary accessories make the fixie low-failure and easy to maintain.
A fixed gear is structurally similar to a road bike – it is built on the basis of a light, compact frame, usually it is almost devoid of accessories, such as fenders or front brakes. The fixed gear system requires the cyclist to pedal constantly, but thanks to it, he can do a stand-up on his “fixed” bike (stand on the bike in place without getting off it) or go backwards.
Construction of a fixed gear bicycle
Fixed gear, derived from track and road bikes, usually has a classic, stiff and light frame modeled on them. The steering wheel may be in the form of a lamb used in cycling bikes, but in urban fixies it is often straight and shortened.
The most important element of OK, as well as of any bike, is the bottom bracket – currently hollowtech or hollowtech II systems are more and more often used here. The nature of driving is determined by the gear ratio used in the running gear, i.e. the ratio of the size (number of teeth) to the racks used. The standard layout is 2.8, but the choice of ratio is an individual matter – thanks to it, you can adjust the ease of pedaling or the ability to achieve higher speeds.
Fixie is based on 28-inch wheels with thin tires to reduce drag. In a fixed gear, the selection of pedals that must stick to the foot is also important: they can have straps or the SPD system known from road bikes.
Despite the simplicity, the design of the fixed gear allows you to adjust the bike to the construction, preferences, riding technique and skills of the rider through the appropriate selection of components.