Abstract: An engine control device for a vehicle is provided, which comprises a control unit configured to be connected to the engine of a vehicle and to control the switching of the engine from a first idle rotation speed to a second idle rotation speed in which the number of engine revolutions is lower compared to the number of revolutions of the first idle speed. The control device also includes a first sensor, configured to be connected to the engine and to instantaneously sense and transmit to the control unit the number of revolutions completed by the engine in the unit of time. The control device further includes a second sensor for detecting the presence of an operator at the vehicle controls, and the second sensor is configured to transmit to the control unit a signal indicating the presence of an operator at the vehicle controls.

Abstract: A method is described for operating a vehicle fitted with a continuously variable transmission (CVT) and having a lever for varying the transmission ratio of the CVT to permit the vehicle operator to vary the vehicle wheel speed. In the invention, the transmission ratio of the CVT is limited to a value dependent upon at least one of the prevailing engine speed and the rate of change of the engine speed.

Abstract: An engine control device for a vehicle is provided, which comprises a control unit configured to be connected to the engine of a vehicle and to control the switching of the engine from a first idle rotation speed to a second idle rotation speed in which the number of engine revolutions is lower compared to the number of revolutions of the first idle speed. The control device also includes a first sensor, configured to be connected to the engine and to instantaneously sense and transmit to the control unit the number of revolutions completed by the engine in the unit of time. The control device further includes a second sensor for detecting the presence of an operator at the vehicle controls, and the second sensor is configured to transmit to the control unit a signal indicating the presence of an operator at the vehicle controls.

Abstract: A system and method for controlling the torque transferable by a mechanical drive between an engine and a shaft of a vehicle includes a first actuator which acts on a variable-speed drive, a second actuator which acts on a clutch to determine the degree of engagement/release of the clutch; and a measuring device for measuring the torque to or from the variable-speed drive. The first and second actuators and the measuring device are controlled by an electronic central control unit to protect the variable-speed drive and/or the clutch from mechanical overloading of the mechanical drive.

Abstract: A method is described for operating a vehicle fitted with a continuously variable transmission (CVT) and having a lever for varying the transmission ratio of the CVT to permit the vehicle operator to vary the vehicle wheel speed. In the invention, the transmission ratio of the CVT is limited to a value dependent upon at least one of the prevailing engine speed and the rate of change of the engine speed.

Abstract: A system and method for controlling the torque transferable by a mechanical drive between an engine and a shaft of a vehicle includes a first actuator which acts on a variable-speed drive, a second actuator which acts on a clutch to determine the degree of engagement/release of the clutch; and a measuring device for measuring the torque to or from the variable-speed drive. The first and second actuators and the measuring device are controlled by an electronic central control unit to protect the variable-speed drive and/or the clutch from mechanical overloading of the mechanical drive.