Two-wheel-drive (2WD) denotes

vehicles A vehicle (from la, vehiculum) is a machine that transports people or cargo. Vehicles include wagons, bicycles, motor vehicles (motorcycles, cars, trucks, buses, mobility scooters for disabled people), railed vehicles (trains, trams), ...

with a

drivetrain A drivetrain (also frequently spelled as drive train or sometimes drive-train) is the group of components that deliver mechanical power from the prime mover to the driven components. In automotive engineering, the drivetrain is the components o ...

that allows two wheels to be driven, and receive

power Power most often refers to: * Power (physics), meaning "rate of doing work" ** Engine power, the power put out by an engine ** Electric power * Power (social and political), the ability to influence people or events ** Abusive power Power may a ...

and

torque In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of th ...

from the

engine An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ...

, simultaneously.

Four-wheeled vehicles

For four-wheeled vehicles (and by extension, vehicles with six, eight, or more wheels), this term is used to describe vehicles that are able to power at most two wheels, referred to as either

front Front may refer to: Arts, entertainment, and media Films * ''The Front'' (1943 film), a 1943 Soviet drama film * ''The Front'', 1976 film Music * The Front (band), an American rock band signed to Columbia Records and active in the 1980s and e ...

, or

rear-wheel-drive Rear-wheel drive (RWD) is a form of engine and transmission layout used in motor vehicles, in which the engine drives the rear wheels only. Until the late 20th century, rear-wheel drive was the most common configuration for cars. Most rear-wheel ...

. The term 4x2 is also used, to denote four total wheels with two being driven. Most road vehicles use a 2WD layout due to its lightweight and simplicity. Traction on the road is usually sufficient that the driving force can be reliably transmitted through only two wheels. For vehicles that have part-time

four-wheel drive Four-wheel drive, also called 4×4 ("four by four") or 4WD, refers to a two-axled vehicle drivetrain capable of providing torque to all of its wheels simultaneously. It may be full-time or on-demand, and is typically linked via a transfer cas ...

, the term refers to the mode when 4WD is deactivated and power is applied to only two wheels.

Two-wheeled vehicles

For two-wheeled vehicles such as

motorcycles A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising ...

and

bicycles A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist. Bi ...

, the term is used to describe vehicles that can power the front as well as the back wheel. The term 2x2 is also used to denote two total wheels with both being driven. 2x2 vehicles are typically either mechanically driven, via a chain,

belt Belt may refer to: Apparel * Belt (clothing), a leather or fabric band worn around the waist * Championship belt, a type of trophy used primarily in combat sports * Colored belts, such as a black belt or red belt, worn by martial arts practit ...

, or shaft, or are hydraulic-driven. This scheme greatly improves offroad performance, but is quite complicated and requires more power to operate, thus most 2WD machines are either "exotic" bikes for enthusiasts or created with special uses in mind. Manufacturers who have one in production include Rokon, Jeep, Tarus and Christini. Manufacturers who are working or have worked on a prototype include ZID, Suzuki,

Yamaha Yamaha may refer to: * Yamaha Corporation, a Japanese company with a wide range of products and services, established in 1887. The company is the largest shareholder of Yamaha Motor Company (below). ** Yamaha Music Foundation, an organization estab ...

KTM KTM AG (Kraftfahrzeug Trunkenpolz Mattighofen, formerly KTM Sportmotorcycle AG) is an Austrian motorcycle, bicycle and sports car manufacturer owned by Pierer Mobility AG and the Indian manufacturer Bajaj Auto. It was formed in 1992 but traces ...

Honda is a Japanese public multinational conglomerate manufacturer of automobiles, motorcycles, and power equipment, headquartered in Minato, Tokyo, Japan. Honda has been the world's largest motorcycle manufacturer since 1959, reaching a producti ...

, and Nissan.

Two-wheel-drive with sidecars

For three-wheeled vehicles such as

motorcycle A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising ...

s with

sidecar A sidecar is a one-wheeled device attached to the side of a motorcycle, scooter, or bicycle, making the whole a three-wheeled vehicle. A motorcycle with a sidecar is sometimes called a ''combination'', an ''outfit'', a ''rig'' or a ''hack''. ...

s, the term is used to describe vehicles that can power the sidecar as well as the back wheel. Sidecar-drive vehicles are typically mechanically driven via a shaft and may or may not have a differential. This scheme greatly improves offroad performance, but is more complicated and requires more power to operate, thus most 2WD machines are vehicles created with special uses in mind such as trials or military use. The first use of the sidecar drive appears in 1928 with the apparent independent invention of

Baughan Baughan was a British cyclecar and motorcycle manufacturer in business from 1920 until 1936. Founded in 1920 in Harrow, Middlesex, from 1921 the company moved to Stroud, Gloucestershire. After motorcycle production finished the company contin ...

in the UK, and Mokharov in the

USSR The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...

References

External links

A brief history of 2x2 motorcycles

KTM shows a new all-wheel-drive motorcycle under development

Christini All Wheel Drive Motorcycles

The Dryvtech 2x2x2 Experimental, a 2x2 motorcycle with two-wheel steering
{{Automobile configuration Car layouts Motorcycle transmissions

Four-wheeled vehicles

Two-wheeled vehicles

Two-wheel-drive with sidecars

See also

References

External links