Device for controlling the speed of an internal combustion engine

A device (10) for controlling the speed of an internal combustion engine comprising a control lever (20) movably associated to a support element (11), which may be the engine casing (101) or a portion thereof. The control lever (20) is moveable at least between a first position, in which the engine is at a first rotation regime, and a second position, in which the engine is at a second rotation regime. A selective locking mechanism (51,521,522) is provided that prohibits the control lever (20) from being stably positioned at any (and all) intermediate positions between the first and second positions. In one embodiment, a biasing force generated by the device (10) automatically forces the control lever (20) into one of the first or second positions when the control lever (20) is located in any of the intermediate positions and an actuation force is ceased.