Influences of aerodynamic drag, the suspension system and rider’s body position on instabilities in a modern motorcycle

Abstract

An approach of analysing the stability and bifurcations of a multibody system previously developed is applied to a model for a modern motorcycle. The model includes a suspension system and aerodynamic drag. Conditions of running straight ahead on a level road at a constant forward speed and cornering in a curve with constant radius are analysed. The drag force, in combination with the suspension system, gives an increased region of stability, and the suspension system in itself prevents the loss of contact between tyres and road in the resulting periodic solutions after the stability limit has been reached.

Keywords:

• Motorcycle dynamics
• Stability
• Wobble
• Weave

Acknowledgements

This work has been supported by a research grant from the Engineering and Physical Sciences Research Council (EPSRC) of the UK.