3- Your link to the road - TIRES - Its all about traction

Your link to the road - TIRES

Tires are a car's direct link to the road. No matter how powerful an engine or how superior a car's suspension may be, nothing else matters unless the tires are up to the challenge.

• The most important piece of equipment on a sports car is said to be its tires. Whether it's accelerating, braking, or turning, all racing actions depend on the traction between a car's tires and the road. This traction (or friction) has two components, a straight-line component and a lateral component, illustrated by the friction circle on this page.

The vertical line represents the friction associated with acceleration and deceleration; the horizontal line represents the friction of left and right turning. If the forces acting on a car exceed the traction between the road and tires, the car will start slipping. This limit where slipping begins is represented by the friction circle. Everything within the circle is less than the car's limit. When a car starts slipping, you'll hear Accelerating familiar skidding sounds. Slight skidding noises indicate that the car is right at the limit of the friction circle. Loud skidding noises mean that the car's limits have been exceeded. Of course, to drive as Right Turning fest as possible, you must be able to drive the car right to its friction limit. To brake in the shortest distance possible, you must use the tires' gripping ability all the way to point C. Any point within the circle does not take full advantage of the tires' Braking traction capacity. Anything outside the circle induces slipping and potential tire locking, greatly increasing braking distance.

If you exceed the car's turning ability, which is represented by the horizontal axis in the figure, the car may not respond to the steering wheel and may go into a spin. It gets a little more difficult when discussing the areas of the friction circle which do not lie on the vertical or horizontal axis. This is because once you leave either of these axes, the forces acting on the tires become a combination of both acceleration/deceleration and turning.

Actions such as braking while turning right or accelerating while turning left are represented on the friction circle by areas that do not lie on the vertical or horizontal axis. Our previous example of applying the brakes to 100% of the tires' traction capacity took us to point C on the figure. If while braking we were to turn the car to the right just a little, we would now move from point C to a point still on the friction circle a bit closer to point B. Thus, our braking ability would decrease slightly while turning as opposed to braking without turning.

If the friction circle represents 100% or our total traction capacity and we use 10% of that traction to turn right, then we would only have 90% traction available for braking.

If we use 100% traction for braking, then 0% is available for turning. In other words, you would not be able to turn at all. If you want to turn slightly while braking, you must ease up on the brakes a little to avoid using them 100%. The same logic applies for turning while accelerating.

In race car driving, it is most common to accelerate/brake and turn In combination, thus creating a variety of forces on your tires. To drive as fast as possible, you must push your car continuously to its performance limit.

Always remember to use the tires' traction all the way to the edge of the friction circle.