Optimization of the Bicycle Weave and Wobble Modes

Stability of bicycles has been studied by using models that assume both a rider with hands-off and hands-on the handlebars. Some authors have presented a general comparison between the behavior of the modes of vibration which affect stability in the two configurations; nonetheless, a systematic analysis of the influence of several parameters on each configuration has not been addressed. In addition, the concept of self-stability range has been used as a stability indicator especially when analyzing a rider’s hands-off situation. In contrast, in this paper, the stability area concept is used as a stability index given that it provides more information about the vibration modes in a broader speed range. Therefore, this paper has two major aims. First, the different influence on stability indexes of geometrical, compliance and tire parameters of road racing bicycles is analyzed using hands-off and hands-on models previously published in the literature. Numerical results show that some parameters have different effects on the stability of weave and wobble modes in hands-off and hands-on conditions. Second, a trade-off between the stability behavior of weave and wobble modes is found when using the hands-on model. Therefore, a multi-objective optimization problem for maximizing the stability of both modes is addressed. A Pareto front of the stability of weave and wobble modes is found that serves to analyze the stability trade-off.