A simple guide to the science of tyre tread patterns. …and why they could save your life!
You have probably noticed that many road vehicles today are fitted with tyres displaying various ‘patterns’ in their tread designs. You may or may not be aware that these patterns are decorative and functional. They are designed to suit different types of driving conditions and vehicle usage. Knowing these differences will enable the driver to make the best choice when buying replacement tyres for his car, van, 4×4 vehicle, etc.
The tread pattern of a tyre is the last thing you want to skimp on when choosing tyres for your performance car. This might sound silly or obvious but many people do! The tread pattern not only serves as the sole interface between your car and the road, but it can also be an integral part of vehicle control in certain situations depending on its design and construction.
Aerodynamics is another important reason why good tread patterns are essential especially for high power applications with high top speeds where aerodynamic drag can find its way into every nook and cranny. Exposed wheel wells with exposed Tyres Online Manchester, that aren’t shielded by skirts or fender flares or covered by body panels will rob your car an additional 5% -10% in aerodynamic efficiency. It might not sound like much but it can be several car lengths over the course of a quarter-mile!
Pattern designs have developed over many years of testing by vehicle manufacturers. They are not only used to increase traction under various driving conditions but also to minimize aquaplaning (when the tyres lose contact with the road surface causing the car or van to skid across the surface like a flat stone skimming water) and improve high-speed stability (especially when negotiating tight bends).
The patterns may be straight or directional; parallel ridged bars; diagonal; tessellated (also called herringbone); circumferential; deep circumferential grooves; or any combination of these features. Each design is specifically tailored for the different types of vehicle and roadway surface requirements.
The ‘straight’ or non-directional pattern is excellent for dry, hard roads where stability is not an issue. These tyres should give good service on showroom floors when new; but should always be checked carefully before fitting them to a car, van, or 4×4 for use in wet weather conditions (see our article here).
The number of grooves will vary depending on the particular tyre manufacturer, but if too few are fitted, they may well cause aquaplaning problems – especially when braking hard while travelling at speed (100kph) on concrete highways with their high levels of friction under heavy braking. A good example would be the Michelin X-Ice.
However, if there are too many grooves, they may well cause a reduction in braking and handling ability on dry roads.
The parallel bar design is also an excellent pattern for concrete or tarmac roads, whether in summer or winter. These Tyres Stockport generally have straight directional bars that run along the centre of the tread, giving them excellent stability during cornering at high speeds on wet roads (i.e., greater than 100kph).
The diagonal pattern will give even better stability. Still, they are usually more expensive due to their complex construction involving rubber compounds tailored especially for use on snow-covered surfaces with reduced friction levels.
They are not generally recommended for use by motorists who do not live in regions where snowfall is common because of the high cost. If they are fitted, it is imperative to check them carefully before use in wet weather (see our article here).
The tessellated pattern is widely used for 4x4s and passenger cars in northern regions where winter conditions prevail with their tendency towards ice, snow, or shallow temperatures. The alternating rigid blocks give extra grip when accelerating on packed snow-covered surfaces.
Still, if the road surface becomes rough because of ploughing operations, it can cause problems by digging into soft earth/sand mixed with stones making it challenging to steer the vehicle at slow speeds.
It’s important to remember that these tyres must not be used on roads where there is an accumulation of compacted snow or ice because their grooves will tend to ice up, making them extremely hazardous. These patterns are often found on the more popular 4×4 vehicles – for example, on Land Rovers.