# Camber angle

Camber angle is one of the angles made by the wheels of a vehicle; specifically, it is the angle between the vertical axis of a wheel and the vertical axis of the vehicle when viewed from the front or rear. It is used in the creation of steering and suspension. If the top of the wheel is farther out than the bottom (that is, tilted away from the axle), it is called positive camber; if the bottom of the wheel is farther out than the top, it is called negative camber. [1]

## Effect on handling

Camber angle alters the handling qualities of some suspension designs; in particular, negative camber improves grip in corners especially with a short long arms suspension. This is because it places the tire at a better angle to the road, transmitting the centrifugal forces through the vertical plane of the tire rather than through a shear force across it. The centrifugal (outwards) force is compensated for by applying negative camber, which turns the contact surface of the tire outwards to match, maximizing the contact patch area. Note that this is only true for the outside tire during the turn; the inside tire would benefit most from positive camber  again, only with a short long arms system. However, due to the weight transfer inherent while turning, the outside wheels bear more of the force of turning and negative camber will improve handling overall. Caster angle will also compensate for this to a degree, as the top of the outside tire will tilt slightly inward, and the inner tire will respectively tilt outward. However, any camber affects the contact patch of the tire while driving in a straight line. Zero camber gives the best traction as it maximises the contact patch between the road and the tires and puts the tire tread flat on the road. Therefore excessive camber impairs straight driving in rain and snow and when accelerating hard.

Proper management of camber angle is a major factor in suspension design, and must incorporate not only idealized geometric models, but also real-life behavior of the components; flex, distortion, elasticity, etc. What was once an art has become much more scientific with the use of computers, which can optimize all of the variables mathematically instead of relying on the designer's intuition and experience. As a result, the handling of even low-priced automobiles has improved dramatically. Heavy-duty vehicles, such as tractors, trucks, etc., tend to have more positive camber angle, so that when they are loaded and the whole vehicle lowers, the wheels are almost vertical.

## Camber in uneven terrain

Off-road vehicles such as agricultural tractors generally use positive camber. In such vehicles, the positive camber angle helps achieve a lower steering effort. Also, some single-engined general-aviation aircraft that are primarily meant to operate from unimproved surfaces, such as bush planes and cropdusters, have their taildragger gear's main wheels equipped with positive-cambered main wheels to better handle the deflection of the landing gear, as the aircraft settles on rough, unpaved airstrips.

## Camber wear

If excessive camber  either positive or negative  is applied, the vehicle's tires will wear unevenly, a condition known as "camber wear".

A suspension with excessive negative camber places more load on the inboard shoulder of the tire, causing the inboard shoulder to wear out quicker than the outboard shoulder. Depending on suspension design, a minor negative camber setting may slightly improve tire wear, as during turns the vehicle's center of gravity shifts toward the outside of the outer wheel. On a vehicle with zero camber this places load on the outboard shoulder of the tire, causing uneven wear over time. A small negative camber angle allows this load to be more evenly distributed across the tread.

Positive camber will generally place more load on the outboard shoulder, causing it to wear more quickly than the inboard shoulder. This is among the many reasons vehicles are not typically aligned with extreme positive or negative camber settings from the factory.

## Stance cars

Negative camber was primarily used in motor sports due to the traction increase around turns. However, it eventually became popular to use negative camber in order to be able to lower a car and fit wheels on it which would not normally fit in the fender wells. Cars with these modifications eventually were given the name "stance cars". It is difficult to pinpoint when exactly this trend began, although it became mainstream in the 1970s with the bōsōzoku cars coming out of Japan. This trend began with the intent of making street cars look more like race cars by lowering their suspension and adding a little negative camber. As time went by, such cars were being customarily lowered more and more, as well as having much more negative camber than before. With the growing of stance-car culture, it also attracted criticism, since extreme amounts of negative camber and minimal ground clearance can makes these cars rather impractical. Accordingly they occasionally became the subject of ridicule from other car enthusiasts, who enjoyed sharing videos of such cars getting stuck on speed bumps.

## Notes

1.^ While nearly all automobiles now use "negative camber" on all four wheels, this convention dates from a time period when positive camber was more common.