Dynamic Analysis and Design of Motorcycle Mounting System Subjected to Road Loads

Abstract

This paper presents a comprehensive model of a motorcycle mounting system. The model presented herein consists of two main assemblies. The powertrain assembly and the swing-arm assembly are modeled as a six degree of freedom rigid bodies. The two assemblies are connected to each other using a shaft that is usually referred to as the coupler. The connection points on both assemblies are known. Unlike automobiles, motorcycle performance and handling is highly affected by the external disturbance. In addition to minimizing the shaking loads, the mounting system must be set up such that it also minimizes the external disturbance from the environment such as irregularities in the road profile and road bumps. This disturbance can be transmitted through the tire patch to the engine causing it to hit nearby components. The engine movement needs to be minimized due to space limitations surrounding the engine. In order to do so, these transmitted external loads must be minimized by the use of the mounting system. The load minimization process is achieved by selecting the optimum stiffness parameters, location and orientation of the mounting system that are supporting the engine. This goal is achieved by an optimization scheme that guarantees that the transmitted loads are minimized. An investigation will be done to explore the effect of different road profiles on the mount final geometrical shape.