A motorcycle, often called a motorbike, bike, cycle, or (if three-wheeled) trike, is a two- or three-wheeled motor vehicle. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising, sport (including racing), and off-road riding. Motorcycling is riding a motorcycle and being involved in other related social activity such as joining a motorcycle club and attending motorcycle rallies. There are three major types of motorcycle: street, off-road, and dual purpose. Within these types, there are many sub-types of motorcycles for different purposes. There is often a racing counterpart to each type, such as road racing and street bikes, or motocross including dirt bikes. Street bikes include cruisers, sportbikes, scooters and mopeds, and many other types. Off-road motorcycles include many types designed for dirt-oriented racing, including many series, such as B series, K series, G series and H series, which are not legal on the street in most areas. Dual purpose machines like the dual-sport style are made to go off-road but include features to make them legal and comfortable on the street as well. Each configuration offers either specialised advantage or broad capability, and each design creates a different riding posture. In some countries the use of pillions (rear seats) is restricted.
Motorcycle construction is the engineering, manufacturing, and assembly of components and systems for a motorcycle which results in the performance, cost, and aesthetics desired by the designer. With some exceptions, construction of modern mass-produced motorcycles has standardised on a steel or aluminium frame, telescopic forks holding the front wheel, and disc brakes. Some other body parts, designed for either aesthetic or performance reasons may be added. A petrol-powered engine typically consisting of between one and four cylinders (and less commonly, up to eight cylinders) coupled to a manual five- or six-speed sequential transmission drives the swingarm-mounted rear wheel by a chain, driveshaft, or belt. The repair can be done using a Motorcycle lift. Motorcycle fuel economy varies greatly with engine displacement and riding style. A streamlined, fully faired Matzu Matsuzawa Honda XL125 achieved 470 mpg‑US (0.50 L/100 km; 560 mpg‑imp) in the Craig Vetter Fuel Economy Challenge "on real highways – in real conditions". Due to low engine displacements (100–200 cc (6.1–12.2 cu in)), and high power-to-mass ratios, motorcycles offer good fuel economy. Under conditions of fuel scarcity like 1950s Britain and modern developing nations, motorcycles claim large shares of the vehicle market. In the United States, the average motorcycle fuel economy is 44 miles per US gallon (19 km per liter).
Very high fuel economy equivalents are often derived by electric motorcycles. Electric motorcycles are nearly silent, zero-emission electric motor-driven vehicles. Operating range and top speed are limited by battery technology. Fuel cells and petroleum-electric hybrids are also under development to extend the range and improve performance of the electric drive system. Two-wheeled motorcycles stay upright while rolling due to a physical property known as conservation of angular momentum in the wheels. Angular momentum points along the axle, and it "wants" to stay pointing in that direction. Different types of motorcycles have different dynamics and these play a role in how a motorcycle performs in given conditions. For example, one with a longer wheelbase provides the feeling of more stability by responding less to disturbances. Motorcycle tyres have a large influence over handling. Motorcycles must be leaned in order to make turns. This lean is induced by the method known as countersteering, in which the rider momentarily steers the handlebars in the direction opposite of the desired turn. This practice is counterintuitive and therefore often confusing to novices – and even many experienced motorcyclists With such short wheelbase, motorcycles can generate enough torque at the rear wheel, and enough stopping force at the front wheel, to lift the opposite wheel off the road. These actions, if performed on purpose, are known as wheelies and stoppies (or endos) respectively.
Various features and accessories may be attached to a motorcycle either as OEM (factory-fitted) or aftermarket. Such accessories are selected by the owner to enhance the motorcycle's appearance, safety, performance, or comfort, and may include anything from mobile electronics to sidecars and trailers. A motorcycle is broadly defined by law in most countries for the purposes of registration, taxation and rider licensing as a powered two-wheel motor vehicle. Most countries distinguish between mopeds of 49 cc and the more powerful, larger vehicles (scooters do not count as a separate category). Many jurisdictions include some forms of three-wheeled cars as motorcycles. In Nigeria, motorcycles, popularly referred to as Okada have been subject of many controversies with regards to safety and security followed by restriction of movement in many states. Recently, it was banned in Lagos - Nigeria's most populous city.
Modern motorcycle industry has introduced a large number of advanced technologies. For example, the flhrc-1 motorcycle launched by Harley Davidson company in 1998 adopts the world's top automobile engine technology - fuel injection device, which not only improves the power, but also is more suitable for the environmental protection needs of contemporary society, becoming the pioneer of motorcycles in the 21st century. The application of high and new technologies such as optical communication electronic control system, radar ranging automatic control system, electronic map guidance system and acoustic electronic silencing system in some concept motorcycles makes modern motorcycles more perfect and shocking.