Abstract

Interactions between the tire and wheel of an assembly are adding extra nonuniformities to those of the tire and wheel themselves. The additional nonuniformities are not small. In one example their average effect on the radial force was 25 to 30 N for two commercial wheels, and 10 N for a precision‐machined wheel.

Interaction forces are acting randomly and hence are seriously disturbing any tire‐wheel matching effort. A simple statistical model is suggested, describing their distribution and allowing an estimation of their effects on tire‐wheel matching.

At this time no leading cause for the existence of interaction forces is known; they seem to accrue from many different minor sources. It is to be hoped that the continuous refinements achieved in the tire and wheel manufacturing processes will eventually reduce all non‐uniformities, including interaction forces, to levels that would render tire‐wheel matching unnecessary.