In motor racing, vehicle setup is the personalised settings on the vehicle which help the vehicle handle and perform predictably and quickly. Vehicle setups are variable for a variety of reasons, ranging from weather, driver/rider preference and race track characteristics. Contrary to common misperceptions, setup is not used to maximize the performance of the engine, but to optimize it for the track at which it is being used. For example, motorcycle racers frequently detune their engines to reduce performance and power output so as to ensure the bike accelerates in a predictable manner.
Usually adjustable vehicle parts include shock absorbers and anti-roll bar (suspension), gear ratios and differential, tyre pressures and type, wing angles, wheel toe and camber angle, brake bias, steering lock and ride height.