Abstract: A clutch having: a fixed hub, a movable hub, and a plurality of plates interposed to selectively transmit a torque. The clutch has a centrifugal pressure plate assembly having: a mass carrier; a plurality of radially movable mass elements, in which each mass element has a pivot connected to the mass carrier for displacement towards an external position under centrifugal effects; wherein the mass elements are further configured to exert axial thrust on a thrust surface of the centrifugal pressure plate assembly, to bring the movable hub closer to the fixed hub and increase the variable axial load. Each mass element has at least one respective rolling element in contact with the thrust surface. The thrust surface has a profile that is sloped and raised towards the external position.

Abstract: A clutch having: a fixed hub, a movable hub, and a plurality of plates interposed to selectively transmit a torque. The clutch has a centrifugal pressure plate assembly having: a mass carrier; a plurality of radially movable mass elements, in which each mass element has a pivot connected to the mass carrier for displacement towards an external position under centrifugal effects; wherein the mass elements are further configured to exert axial thrust on a thrust surface of the centrifugal pressure plate assembly, to bring the movable hub closer to the fixed hub and increase the variable axial load. Each mass element has at least one respective rolling element in contact with the thrust surface. The thrust surface has a profile that is sloped and raised towards the external position.

Abstract: A motorcycle including a frame to which an internal combustion engine is associated, from which internal combustion engine at least one exhaust pipe of combusted gases departs, the exhaust pipe having an open terminal, the frame mounted on a front wheel and a rear wheel, a control board or unit included, for controlling torque produced by the engine and other parameters such as velocity of the vehicle and spatial position thereof with respect to the road surface. The motorcycle including a system to verify when the front wheel of the motorcycle detaches from the road surface during acceleration. The system includes a choke for partializing the section of the exhaust gases outlet area from the exhaust pipe, during partialization. The partialization obtained as a function of the torque produced by the engine and the position of the front wheel with respect to the road surface.

Abstract: A motorcycle including a frame to which an internal combustion engine is associated, from which internal combustion engine at least one exhaust pipe of combusted gases departs, the exhaust pipe having an open terminal, the frame mounted on a front wheel and a rear wheel, a control board or unit included, for controlling torque produced by the engine and other parameters such as velocity of the vehicle and spatial position thereof with respect to the road surface. The motorcycle including a system to verify when the front wheel of the motorcycle detaches from the road surface during acceleration. The system includes a choke for partialising the section of the exhaust gases outlet area from the exhaust pipe, during partialisation. The partialisation obtained as a function of the torque produced by the engine and the position of the front wheel with respect to the road surface.