Bits and Pieces Tyres - Part 1

Over the next few editions Bits and Pieces will explore the black and sticky world of bike tyres. Here we contrast road and race tyres in terms of design criteria, performance and functionality.
While race tyres feature the latest in design technology, it is in fact road tyres that pose a greater or certainly more complex challenge to manufacturers such as Pirelli. As road conditions and rider demands are much more variable than a race track environment, a high performance road tyre needs to balance many more, often conflicting requirements. A road tyre needs a high level of ride quality and rider feedback, coupled with durability and the capability to handle all road surfaces and weather conditions. These are less important in racing where tyres are developed to provide the ultimate performance for a specific circuit and weather conditions.

As you might expect the riding style is also totally different. During cornering, racers have little interest in the progression of lean angles on a front tyre. In racing conditions, the tyre will go almost instantaneously from the vertical to the shoulder where riders demand maximum lean grip. Road machines require light, progressive handling with reliable corner entry stability. A road rider will use all of the intermediate lean angles and will expect consistent grip irrespective of the lean angle as well as neutral steering characteristics from the upright all the way down to the shoulder.

Obviously designers of high performance road tyres are trying to preserve as much race tyre performance as possible while engineering the new tyre to meet the stability, durability and wet-weather performance levels of road bike enthusiasts. Itนs not just marketing as race tyre design elements really are adapted from their original form to address the requirements of road legal uses.

Regardless or race or road usage, new performance tyres have to be developed to cope with the ever increasing demands of modern bikes such as Hondaนs CBR 600 RR. These machines have higher power, less weight and improved chassis giving performance levels higher than ever before. In recent years some machines have seen as much as a 60% increase in power to weight ratio over their predecessors and tyres form the only link to the tarmac!