Abstract

Water on a road surface can dangerously lower the coefficient of friction of vehicle tires. One way to reduce the water thickness is to cut many “rain grooves” into the pavement parallel to its edges. Such grooves, however, can exert unwanted side forces, particularly on motorcycle tires where driver reaction can cause accidents. This “grove wander” is somewhat related to vehicle geometry, but is more strongly related to interaction between road grooves and tire tread grooves. From studies of this interaction we have developed principles for tread groove design that can be evaluated from relative spacing of tread grooves and pavement grooves, as well as by subjective road tests.