Computer-Aided Analysis and Experimental Verification of a Motorcycle Suspension

A computer-aided analysis and experimental verification of a motorcycle suspension are presented. A mathematical model describing the flow characteristics in a front fork and a rear shock absorber was independently developed for both compression and extension strokes. The model includes both laminar and turbulent flow conditions and the spring effect due to entrapped air in front fork and gas charged chamber in the case of rear shock absorber. A sinusoidal displacement was considered as the input excitation for the model. A digital simulation in the case of front fork and an analog simulation for rear shock absorber were used to obtain force-displacement (F-D) Lissajous diagrams for each input amplitude-frequency combination. An experimental setup consisting of an electro-hydraulic shaker was used to test the performance characteristics of the front fork and rear shock absorber. The comparison between simulated and experimentally obtained results is presented and discussed.