Effectiveness of the Basic Model for Motorcycle Dynamics

Abstract

A basic motorcycle dynamics model having four degrees of freedom was experimentally confirmed in this study. The frequency response functions, damping properties, and natural frequencies of weave and wobble modes which are vibrational modes of straight-running stability, were calculated using this model. Conclusions were drawn about effectiveness of the model from comparing of calculations and running experiments. (1) The four-degree-of-freedom model is effective for predicting steering response of the motorcycle during normal running conditions. (2) The weave mode calculations compare favorably with experiments in damped natural frequency, and agree approximately with experiments in damping ratio. (3) The calculated and experimental values of wobble mode are not necessarily the same with each test vehicle in damped natural frequency, and may differ in damping ratio.