Have you ever seen a tyre which has lost more tread on a certain patch of its circumference than all around? If yes, what you saw is called a flat spot. A flat-spotted tyre is one thing that can spoil the grip level and the ride quality of the vehicle. What’s worse is that it takes only a split second to get flat spots on the tyres.
What is flat-spotting exactly? A flat spot is created on a tyre which is otherwise round after the tyre suffers a lockup while braking or in case the vehicle slides or spins out while the tyres are locked up.
Vehicles that are not equipped with the Anti-lock Braking System (ABS) have a high chance of flat-spotting tyres while performing emergency braking. During the panic braking situation, the instinctive response of a driver is to stomp on the brake pedal. Most of the times, this results to wheel lock-up and tyres get a flat spot as the contact patch sacrifices itself to stop the vehicle.
In an ABS-equipped vehicle, the tyres do not lock-up even if the driver stomps on the brake pedal. This helps to reduce the stopping distance on the slippery roads and it allows the driver to be able to steer the car.
The simplest way of preventing tyre from getting a flat spot is by braking progressively. A driver should always avoid locking up the brakes since it takes away the directional maneuverability and also results in longer stopping distance. However, in case of panic braking, it is not always possible to think about not locking up the brake and the first reaction is to stand on the brake pedal.
Threshold braking is the best method to shed lot of speed quickly. In this technique, the driver needs to develop a good feel for knowing when the the brakes are locking up. This allows him/her to maintain the optimal brake pressure, so the tyres are on the limit of traction before they start to skid across the road. If the brakes do locks-up, reducing the brake pressure slightly can help to regain maximum traction and directional control.
Threshold braking is not a difficult skill to master as it is difficult to get a feel for brakes getting locked-up. In such a case, you can use the brake pumping method. In this, the driver repeatedly increases and reduces the brake pressure, so the contact patch of the tyres does not scruff away on the road for a long time. An ABS system performs the same trick but much more smoothly and effectively.