Analysis of Road Induced Loads in Bicycle Frames

Abstract

A five degree-of-freedom model of a bicycle and rider was developed to investigate the system response to inputs from the road as the first step in a unique fatigue failure analysis of a bicycle frame. Transfer functions relating the induced frame loads and the road input spectra are given, as are the frame load spectra for realistic levels of road inputs. The transfer functions show that the system is lightly damped and responds more strongly to inputs at the rear wheel than to inputs at the front. The load spectra show that the load picture is one of small fluctuations around a relatively large static offset.