A groove is the sunken part of a tyre's tread. Notably grooves are the fundamental components in deciding a tyre's quality. The groove improves the braking performance and driving power of a tyre. Groove depth and design also effects road noise and the rate of a tyre's treadwear.
A sipe is a fine groove in the tread pattern. The function of a sipe is to enhance braking and driving performance, and to provide driving stability and comfort. In the case of winter tyres it allows grip on icy conditions through the biting effect of the edge, and also improves braking control wet roads.
Rib shape : The pattern along the circumference of the tyre
Good points : Lower rolling resistance. Good directional stability and steering control thanks to lateral resistance. Suitable for sustained high speeds thanks to low heat generation.
Bad points : Poor braking & acceleration grip on wet roads. Stress caused by flex means tread is more susceptible to cracking.
Use : For paved road surfaces and the steering wheels of trucks or buses
Lug shape : The groove pattern perpendicular to the circumference of the tyre
Good points : Excellent braking & driving power. Superior traction
Bad points : Noisy at high speed. It's not suitable for high speed driving because of high rolling resistance.
Use : For dirt roads, rear wheels of buses, industrial vehicles and dump trucks.
Rib-Lug shape : The combination of Rib-shape & Lug-shape
Features : The rib in the centre provides directional control whilst the shoulder lug gives good braking & driving power
Use : Good for both paved and dirt roads. Usually used in both front & rear wheels of trucks and buses.
Block-shape : The pattern of independent block, which the groove is connected with each other
Good points : Good steering control and stability on snow covered and wet roads. Good water dispersal properties on wet roads.
Bad points : Tyre wear is heavy as tread blocks are finer.
Use : Suitable for winter or all-season passenger car tyres. Suitable for back-wheel of Radial tyre of ordinary car
Asymmetric pattern : Tread pattern differs on each side
Good points : Good for high speed cornering thanks to greater contact area. Reduces treadwear on outside of tyre.
Bad points : You must position them the right way around.
Use : High performance and motorsport tyres
Directional pattern : Lateral grooves on both sides point the same direction
Good points : Good driving force and braking performance. Good water dispersal means good stability on wet roads. Correct choice for fast driving styles.
Features : mounted in direction of tread pattern
Use : the passenger car tyre for high speed usage.