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.

A cover for a utility enclosure includes a cover having a top, a bottom, a front side, a rear side, a left side, and a right side, defining an interior. The cover further includes a plurality of ribs in the interior dividing the interior into a plurality of spaces. The cover further includes the top having one or more air vents. The cover further includes the air vents having channels constructed to vent air in the spaces to an exterior of the cover, thereby preventing flotation of the cover in water.

A manhole is provided with a base plate, manhole walls, and a cover plate for covering the manhole. The manhole walls include of a plurality of grid-like wall elements arranged in rows one above the other and selectable from a modular system. A part of the grid-like wall elements has at least one conduit insertion opening so that the position, number, and size of conduit insertions into the manhole walls are freely selectable by arranging the grid-like wall elements. Several circumferential connecting frames are provided, which are arranged at different heights, and the grid-like wall elements are each connected on their top sides and bottom sides to one of the connecting frames.

A cover for an underground enclosure may include an upper surface comprising a pattern of bosses, a first slot and a second slot disposed on the upper surface, a lower surface opposite the upper surface. A first reinforcement member may be coupled to the lower surface. The first slot may extend into the first reinforcement member, and a second reinforcement member may be coupled to the lower surface and aligned with the first reinforcement member. The second slot may extend into the second reinforcement member. The cover may be configured to be lifted by the first slot and the second slot.