Vertical and Longitudinal Characteristics of a Bicycle Tire

Abstract

ABSTRACT Electric bicycles have undergone a real boom in recent years and play an important role in the area of sustainable mobility. In addition to assisting the rider while accelerating the bicycle, the available electrical energy also offers the possibility to deploy safety systems to reduce the risk of accidents. For instance, active safety systems could help to avoid two major critical braking situations for single-track vehicles: front wheel lockup and nose-over (i.e., falling over the handlebars). An essential prerequisite for the development of such systems is a thorough understanding of tire effects on bicycle dynamics. To date, there are only very few scientific studies concerning bicycle tire characteristics. Thus, test runs on an inner drum tire test bench have been performed to measure vertical and longitudinal characteristics of a typical trekking bike tire. This article presents the main findings such as vertical stiffness and contact patch geometry depending on wheel load and inflation pressure as well as characteristic curves of the longitudinal force depending on slip with variation in road condition, wheel load, speed, and inflation pressure. Based on these valuable insights, further improvements are proposed, and an outlook on the next research steps is given.