In this paper, two alternative front suspension sys-
tems and their influence on motorcycle nonlinear dynamics
are investigated. Based on an existing high-fidelity motor-
cycle mathematical model, the front end is modified to ac-
commodate both Girder and Hossack suspension systems.
Both of them have in common a double wishbone design
that varies the front end geometry on certain manoeuvrings
and, consequently, the machine’s behaviour. The kinemat-
ics of the two systems and their impact on the motorcycle
performance is analysed and compared to the well known
telescopic fork suspension system. Stability study for both
systems is carried out by combination of nonlinear dynami-
cal simulation and root-loci analysis methods.