All terrain vehicle

An all-terrain vehicle (ATV), also known as a quad, quad bike, three-wheeler, four-wheeler, or quadricycle as defined by the American National Standards Institute (ANSI) is a vehicle that travels on low-pressure tires, with a seat that is straddled by the operator, along with handlebars for steering control. As the name implies, it is designed to handle a wider variety of terrain than most other vehicles. Although it is a street-legal vehicle in some countries, it is not street-legal within most states and provinces of Australia, the United States or Canada.

By the current ANSI definition, ATVs are intended for use by a single operator, although some companies have developed ATVs intended for use by the operator and one passenger. These ATVs are referred to as tandem ATVs.

The rider sits on and operates these vehicles like a motorcycle, but the extra wheels give more stability at slower speeds. Although equipped with three or four wheels, six-wheel models exist for specialized applications. Engine sizes of ATVs currently for sale in the United States, (as of 2008 products), range from 49 to 1,000 cc (3 to 61 cu in).

Royal Enfield built and sold the first powered quadracycle in 1893. It had many bicycle components, including handle bars. The Royal Enfield resembles a modern ATV-style quad bike but was designed as a form of horseless carriage for road use.

The term "ATV" was originally coined to refer to non-straddle ridden six-wheeled amphibious ATVs such as the Jiger produced by the Jiger Corporation, the Amphicat produced by Mobility Unlimited Inc, and the Terra Tiger produced by the Allis-Chalmers Manufacturing Company in the mid 1960s and early 1970s. With the introduction of straddle ridden ATVs, the term AATV was introduced to define the original amphibious ATV category.

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