Motorized tricycle

Motorized tricycles are three-wheeled vehicles based on the same technology as bicycles or motorcycles, and powered by electric motors, motorcycle, scooter or car engines.

Depending on the design of the vehicle, motorized trikes may be categorized as motorcycles, motor scooters, or simply the three-wheeled counterpart to a motorized or electric bicycle. The main difference between a motorcycle trike and a scooter trike is that motorcycles are sat on in a "saddle"-style seating (as with a horse), with the legs apart, and motorcycles have manual transmissions. Scooters have a "step-through" seating style, in which the driver sits on a more chair-like seat, with the legs together; as well, scooters have automatic transmissions. While laypersons often associate the engine size as a dividing line between motorcycles and scooters, since a typical scooter has a small 50 cc engine, engine size is not one of the dividing lines, because some scooters such as the Burgman have 638 cc engines.

Motorcycles with sidecars are not usually considered tricycles. It can be harder to categorize three-wheeled automobiles. While some early prototype automobiles were steam tricycles, three-wheeled cars such as the Morgan 3-Wheeler are often classified as cars rather than motorcycles.

A motorized tricycle's wheels may be arranged in either configuration: delta or tadpole. A delta trike has one wheel in front and two in back, and the tadpole trike has two wheels in front and one in back. Occasionally, rear wheel steering is used, although this increases the turning circle and can affect handling (the geometry is similar to a regular trike operating in reverse, but with a steering damper added).

Tadpoles are more stable under braking and more likely to slide instead of roll; front braking hard on a delta requires the vehicle to steer almost straight to avoid tipping. The balance of friction patches and rolling resistance also means that tadpoles tend to oversteer and deltas understeer.

Motor trikes are attractive for those with mobility or balance problems.

Under some local regulations, while riding a three-wheeled vehicle, it may be possible to carry multiple passengers with a motorcycle driving license, to ride a motorcycle-style vehicle with a car license, or to avoid motorcycle helmet use regulations.

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