The general trend of the forces generated by a non uniform tire and wheel as a function of speed has been available for several years. As a rule it has been found that the first harmonic of the force variation is the greatest single contributory factor in those vehicle shake problems originating at the tire and wheel. The paper shows how the first harmonic varies with speed for a batch of tires, and, in particular, discusses the phase and amplitude relationship between longitudinal force variation and radial force variation with speed; a mathematical analysis is given.
Abstract