Setup Dev 06 - Caster

Caster is the angle of your steering movement as seen from the side. It provides some self-centering effect while driving in a straight line. An example of extreme positive caster is a chopper motorcycle where it's steering axis is "laying down" at the angle of the motorcycle's forks. An example of negative caster (never ideal in racing) is the front wheels of a shopping cart. They are being "dragged" behind the steering pivot point, often wobbling around and very unstable. More positive caster dials in more self-centering, which can be a good thing for comfort alone.

An added benefit, and more important, is that caster also affects the camber when the wheels are turned. More positive caster gives more negative camber to the outside wheel when in a turn. This allows the option of less static camber in your setup and using more caster to achieve your ideal camber angle. Just as important is how positive caster effects your inside wheel camber. Your inside wheel will lose some of the negative static camber and possibly even go into a positive camber setting which is ideal for your inside wheel while in a corner. The side-effect of added caster is the ability to reduce your static camber settings. While negative camber assists only your outside wheel in a corner, it has a negative effect on the grip of your inside wheel while cornering and both wheels under braking or acceleration. The more camber you can replace with caster the better your front wheels will maintain grip in all situations.

After changing your caster settings, recheck each of your tire temperatures and make pressure changes as needed. You may need to adjust camber settings as well, usually reducing the amount of static camber you have.