The caster angle[1] or castor angle[2] is the angular displacement of the steering axis from the vertical axis of a steered wheel in a car, motorcycle, bicycle, other vehicle or a vessel, as seen from the side of the vehicle. The steering axis in a car with dual ball joint suspension is an imaginary line that runs through the center of the upper ball joint to the center of the lower ball joint, or through the center of the kingpin for vehicles having a kingpin.
Caster causes a wheel to align with the direction of travel, and can be accomplished either by caster displacement or caster angle. Caster displacement moves the steering axis ahead of the axis of wheel rotation, as with the front wheels of a shopping cart. Caster angle moves the steering axis from vertical.[3]
In automobile racing, the caster angle may be adjusted to optimize handling characteristics for a particular venue. This is all connected to the front wheels.
- ^ "Merriam Webster Dictionary". Retrieved 2009-12-25.
caster n : the slight usually backward tilt from vertical of the axis of the steering mechanism of an automobile for giving directional stability to the front wheels
- ^ Oxford English Dictionary (2nd ed.). Oxford University Press. 1989.
castor angle, the angle at which the steering-head of the front wheels of a motor vehicle is set
- ^ Learn Camber, Caster, and Toe, COME AND DRIVE IT, retrieved January 5, 2021