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Abstract

The design of a motorcycle frame has an important influence upon the machine's weave and flutter oscillation characteristics. This paper deals particularly with the torsional stiffness of the frame and it underlines the importance of the position of the axis about which the frame twists.

This concept of a twist axis is introduced by reference to a simple parallel tube structure. It is demonstrated that because the twist axis moves, the torsional stiffness of a structure may reduce as individual members are stiffened. The position of the twist axis of a motorcycle frame is determined by finite element techniques and it is shown that an attempt, without due consideration of the twist axis, to improve its torsional stiffness, in fact has the opposite effect.

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References

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The Relationship between Twist Axis and Effective Torsional Stiffness of a Motorcycle Frame

Abstract

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References