Abstract
The modern tyre may be considered as a compromise, being expected to generate safe values of friction under all conditions of motoring where the inherent frictional properties of the road surface may change abruptly by up to a factor of ten. Unless the road surface possesses the essential microtexture, with the associated required level of macrotexture related to the speed of traffic, surface gradient etc., it is not possible to develop a sufficient level of vehicle roadhold by tyre or brake development alone.