Variation of the Spring Stiffness of the Tire (tire spring rate) cW
In the figure, the spring rate of the tire is varied. A softer tire rate tends to reduce wheel natural frequency and the dynamic wheel loads, i.e. road grip is improved. Softer tires would thus clearly improve driving safety. Realization of such tires is however, only possible within narrow limits due to the associated increase in rolling resistance and flexing energy.