Method to control an optimal apply pressure for the sheaves of a variator in a continuously variable transmission

The optimal pressure acting on the variator of an infinitely variable gear system can be determined by creating a representation of the road surface the vehicle is presently moving along. The average rotation rate of the wheels is established with the use of sensors and the condition of the road determined in relation to peak values of individual wheels indicating irregularities in the surface. After a predetermined time of a low level of irregularities the pressure can be reduced again.