Valve actuation system comprising in-series lost motion components deployed in a pre-rocker arm valve train component and valve bridge

A method of operating an internal combustion engine comprising a cylinder, at least one engine valve associated with the cylinder, a rocker arm, and a single cam configured to provide a main valve actuation motion and an auxiliary valve actuation motion so as to actuate the at least one engine valve via a valve actuation load path comprising a valve bridge and a pre-rocker arm valve train component each operatively connected to the rocker arm, the method comprising:

• providing a lost motion subtracting mechanism arranged in the pre-rocker arm valve train component and configured, in a first default operating state, to convey at least the main valve actuation motion and configured, in a first activated state, to lose the main valve actuation motion and the auxiliary valve actuation motion;
• providing a lost motion adding mechanism arranged in the valve bridge and configured, in a second default operating state, to lose the auxiliary valve actuation motion and configured, in a second activated state, to convey the auxiliary valve actuation motion, wherein the lost motion adding mechanism is arranged in series with the lost motion subtracting mechanism in the valve actuation load path;
• and
• operating the internal combustion engine in:
• a positive power mode in which the lost motion subtracting mechanism is in the first default operating state and the lost motion adding mechanism is in the second default operating state, or
• a deactivated mode in which the lost motion subtracting mechanism is in the first activated operating state and the lost motion adding mechanism is in the second default operating state, or
• an auxiliary mode in which the lost motion subtracting mechanism is in the first default operating state and the lost motion adding mechanism is in the second activated operating state.