A bicycle, also called a pedal cycle, bike, push-bike or cycle, is a human-powered or motor-assisted, pedal-driven, single-track vehicle, with two wheels attached to a frame, one behind the other. A bicycle rider is called a cyclist, or bicyclist.
A mountain bike (MTB) or mountain bicycle is a bicycle designed for off-road cycling. Mountain bikes share some similarities with other bicycles, but incorporate features designed to enhance durability and performance in rough terrain, which often makes them heavier, more complex and less efficient on smooth surfaces. These typically include a suspension fork, large knobby tires, more durable wheels, more powerful brakes, straight, extra wide handlebars to improve balance and comfort over rough terrain, and wide-ratio gearing optimised for topography, application and a frame with a suspension mechanism for the rear wheel. Rear suspension is ubiquitous in heavier-duty bikes and now common even in lighter bikes. Dropper seat posts can be installed to allow the rider to quickly adjust the seat height.
A recumbent bicycle is a bicycle that places the rider in a laid-back reclining position. Some recumbent riders may choose this type of design for ergonomic reasons: the rider's weight is distributed comfortably over a larger area, supported by back and buttocks. On a traditional upright bicycle, the body weight rests entirely on a small portion of the sitting bones, the feet, and the hands.
A bicycle frame is the main component of a bicycle, onto which wheels and other components are fitted. The modern and most common frame design for an upright bicycle is based on the safety bicycle, and consists of two triangles: a main triangle and a paired rear triangle. This is known as the diamond frame. Frames are required to be strong, stiff and light, which they do by combining different materials and shapes.
A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels.
There have been many human powered vehicles designed and constructed specifically for transporting loads since their earliest appearance in the 20th century. They are referred to variously depending on the number of wheels — typically two, three, or four — and by their specific use. Adjectives used to describe the tasks to which the bicycles, dicycles, tricycles, or quadracycles are put include cargo cycles, freight cycles, box cycles, carrier cycles, and so on. Sometimes they are also called cycletrucks, which uses a sense of the word 'truck' predating the automobile.
A touring bicycle is a bicycle designed or modified to handle bicycle touring. To make the bikes sufficiently robust, comfortable and capable of carrying heavy loads, special features may include a long wheelbase, frame materials that favor flexibility over rigidity, heavy duty wheels, and multiple mounting points.
A utility bicycle, city bicycle, urban bicycle, European city bike (ECB), Dutch bike, classic bike or simply city-bike is a bicycle designed for frequent very short, relatively slow rides through very flat urban areas. It is a form of utility bicycle commonly seen around the world, built to facilitate everyday short-distance riding in normal clothes in cold-to-mild weather conditions. It is therefore a bicycle designed for very short-range practical transportation, as opposed to those primarily for recreation and competition, such as touring bicycles, road bicycles, and mountain bicycles. Utility bicycles are the most common form globally, and comprise the vast majority found in the developing world. City bikes may be individually owned or operated as part of a public bike sharing scheme.
A racing bicycle, also known as a road bike is a bicycle designed for competitive road cycling, a sport governed by and according to the rules of the Union Cycliste Internationale (UCI).
Hybrid bicycles blend characteristics from more specialized road bikes, touring bikes and mountain bikes. The resulting "hybrid" is a general-purpose bike that can tolerate a wide range of riding conditions and applications. Their stability, comfort and ease of use make them popular with novice cyclists, casual riders, commuters, and children.
The Birdy is a folding bicycle designed by Riese und Müller in Germany and produced by Pacific Cycles in Taiwan. As of 2010 over 100,000 had been sold. Three distinct models have been marketed, in addition to some specialist variations, with the third (Mk3) introduced in July 2015.
A fork end, fork-end, or forkend is a slot in a bicycle frame or bicycle fork where the axle of a bicycle wheel is attached. A dropout is a type of fork end that allows the rear wheel to be removed without first derailing the chain.
A roadster bicycle is a type of utility bicycle once common worldwide, and still common in Asia, Africa, Latin America, and some parts of Europe. During the past few decades, traditionally styled roadster bicycles have regained popularity in the Western world, particularly as a lifestyle or fashion statement in an urban environment.
A bicycle trailer is a motorless wheeled frame with a hitch system for transporting cargo by bicycle. It can greatly increase a bike's cargo capacity, allowing point-to-point haulage of objects up to 3 cubic metres in volume that weigh as much as 500 kg. However, very heavily loaded trailers may pose a danger to the cyclist and others, and the voluntary European standard EN 15918 therefore suggests a maximum load of 60 kg on trailers without brakes.
Fender is the American English term for the part of an automobile, motorcycle or other vehicle body that frames a wheel well. Its primary purpose is to prevent sand, mud, rocks, liquids, and other road spray from being thrown into the air by the rotating tire. Fenders are typically rigid and can be damaged by contact with the road surface.
Bicycle and motorcycle dynamics is the science of the motion of bicycles and motorcycles and their components, due to the forces acting on them. Dynamics falls under a branch of physics known as classical mechanics. Bike motions of interest include balancing, steering, braking, accelerating, suspension activation, and vibration. The study of these motions began in the late 19th century and continues today.
Motorcycle accessories are features and accessories selected by a motorcycle owner to enhance safety, performance, or comfort, and may include anything from mobile electronics to sidecars and trailers. An accessory may be added at the factory by the original equipment manufacturer or purchased and installed by the owner post-sale as aftermarket goods. The term Farkle is used within the motorcycle community, originally to denote useful add-ons, such as GPS or other upgraded components. Now also used at times in a humorous or mildly derogatory way to describe bling, such as anodized or chromed parts that add no functionality.
The following outline is provided as an overview of and topical guide to bicycles:
