Tire tops can tilt {camber}| out or in, rather than be vertical.
amount
Camber ranges from -1.0 to +1 degrees. Negative camber tilts in. Positive camber tilts out. Positive camber allows better support by wheel bearings.
turn
Tires tend to tilt out toward outside turn, because tread sticks to road and tire top has centrifugal force.
When car body slides toward outside turn, MacPherson strut suspensions tilt tires out, but unequal A-arms tilt tires in. During turns, tire inside or outside can lift off road. Negative camber for MacPherson strut suspensions and positive camber for unequal A-arms allow tires to be vertical during turns, when traction is most important.
pull
If one tire has higher camber, car pulls to that side.
road
Because road crown pulls car to right, in right-hand-drive countries, left tire can require higher camber.
Tires can lean to front or rear {caster, tire}, rather than be vertical. Positive caster is forward tilt. Too much positive caster causes shimmy, because weight falls in front of tread. Too little positive caster causes poor tracking, because weight falls down tire center.
Caster settings typically are 0.5 to 4 degrees. From 3 to 4 results in better straight-line tracking but heavier steering. From 0.5 to 1 makes lighter steering, but poorer straight-line tracking.
Negative caster is backward tilt. Negative caster puts weight behind tire and causes unstable tracking, because it pushes tire forward in various directions.
Tires can swivel left or right, rather than aligning straight-ahead {toe}|. Toe is in or out. It causes stability because, during turns or bumps, tires tend to return to straight-ahead position. At higher speeds, toe becomes slightly more out, so starting slightly in is better. Out is only for front tire center offset or special wheel bearings. Rear tires are neither in nor out, because in or out causes instability and rapid tire wear.
7-Machine-Kinds-Mechanical-Rotation
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Date Modified: 2022.0225