In the drag racing environment, maximizing tractive effort is essential to competitive performance. Anti-squat is a transient vehicle suspension parameter which can dramatically affect tractive effort available at the motorcycle drive tire. This paper addresses the design of a four-link rear suspension for a drag racing motorcycle to provide anti-squat, which increases rear tire traction, thereby improving vehicle acceleration performance. Utilizing PC based CAD, finite element analysis and dynamic system analysis software, a motorcycle rear suspension system was designed, built and tested under actual racing conditions. Parametric studies using dynamic theoretical models were conducted for both unsuspended and four-link equipped versions of the same vehicle. Based on the results, it is shown that the four-link suspension, when applied to a drag racing motorcycle, does provide opportunity for improving tractive effort at the beginning of a race which will improve overall drag racing performance.

Issue Section:
Technical Papers
Keywords:
design engineering, vehicles, finite element analysis, CAD
Topics:
Design, Drag (Fluid dynamics), Dynamic models, Motorcycles, Tires, Vehicles, Wheels
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7.
Wiers, P. C., 1997, “Four-Link Anti-Squat and Drag Racing Motorcycle Performance: A Parametric Study,” M.S. Thesis, University of Wisconsin-Milwaukee.
Copyright © 2002
 by ASME
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