Abstract: The present invention relates to a suspension and steering system enabling the road holding, braking efficiency and safety of presently known cycles and motorcycles of all types, on wheels or on skis, to be increased, while maintaining their capacity to bank when cornering, their handling ability and small dimensions. This system is composed of the combination of two sub-systems:--the suspension sub-system intended to carry two wheels or two skis, comprises: (a) a mechanism composed of two forks, two pairs of guide shafts, and two supports. The forks move over the guide shafts which are fixed to the supports; (b) a mechanism composed of a support, a rocking arm and a handle bar. This arm rocks on the axis of the support and allows the interdependent displacements of the forks;--the steering sub-system is intended on the one hand to carry the above mentioned mechanisms of the suspension sub-system and on the other hand to be articulated on the frame at the steering column and the reinforcing arm.