A valve actuation system for an internal combustion engine, said valve actuation system comprising: • a rocker pivotably mounted around a pivot axis and having: - a driven end portion adapted to cooperate with a rotating cam including a main bump and at least one auxiliary bump (211, 212) having a smaller radial dimension than the main bump; - an actuating end portion equipped with at least one piston adapted to open at least one valve of the engine following the cooperation of the driven end portion with a bump of the cam, the piston being slidably mounted relative to the rocker between an extended position allowing said piston to open said valve when the driven end portion contacts the auxiliary bump (211, 212), and a retracted position preventing said piston to open said valve when the driven end portion contacts the auxiliary bump (211, 212); the rocker comprising: - a fluid circuit for providing a fluid in order to cause the piston to move from its retracted position to its extended position; - a reset circuit comprising a reset valve rotatably mounted relative to the rocker, between an inactive position, and an active position in which the reset valve causes the fluid to be drained out of the fluid circuit to allow the piston to move towards its retracted position; • a lever pivotably mounted around a pivot axis, the lever having a driven end portion adapted to cooperate with a rotating reset cam including at least one bump, and an actuating end portion for rotating the reset valve from its inactive position towards its active position following the cooperation of the lever driven end portion with the bump of the reset cam; the valve actuation system being characterized in that, it comprises • rotational coupling means (75, 95) between the lever and the reset valve, said rotational coupling means having a transmission ratio greater than 1. • a rocker pivotably mounted around a pivot axis and having: - a driven end portion adapted to cooperate with a rotating cam including a main bump and at least one auxiliary bump (211, 212) having a smaller radial dimension than the main bump; - an actuating end portion equipped with at least one piston adapted to open at least one valve of the engine following the cooperation of the driven end portion with a bump of the cam, the piston being slidably mounted relative to the rocker between an extended position allowing said piston to open said valve when the driven end portion contacts the auxiliary bump (211, 212), and a retracted position preventing said piston to open said valve when the driven end portion contacts the auxiliary bump (211, 212); the rocker comprising: - a fluid circuit for providing a fluid in order to cause the piston to move from its retracted position to its extended position; - a reset circuit comprising a reset valve rotatably mounted relative to the rocker, between an inactive position, and an active position in which the reset valve causes the fluid to be drained out of the fluid circuit to allow the piston to move towards its retracted position; - a driven end portion adapted to cooperate with a rotating cam including a main bump and at least one auxiliary bump (211, 212) having a smaller radial dimension than the main bump; - an actuating end portion equipped with at least one piston adapted to open at least one valve of the engine following the cooperation of the driven end portion with a bump of the cam, the piston being slidably mounted relative to the rocker between an extended position allowing said piston to open said valve when the driven end portion contacts the auxiliary bump (211, 212), and a retracted position preventing said piston to open said valve when the driven end portion contacts the auxiliary bump (211, 212); - a fluid circuit for providing a fluid in order to cause the piston to move from its retracted position to its extended position; - a reset circuit comprising a reset valve rotatably mounted relative to the rocker, between an inactive position, and an active position in which the reset valve causes the fluid to be drained out of the fluid circuit to allow the piston to move towards its retracted position; • a lever pivotably mounted around a pivot axis, the lever having a driven end portion adapted to cooperate with a rotating reset cam including at least one bump, and an actuating end portion for rotating the reset valve from its inactive position towards its active position following the cooperation of the lever driven end portion with the bump of the reset cam; the valve actuation system being characterized in that, it comprises • rotational coupling means (75, 95) between the lever and the reset valve, said rotational coupling means having a transmission ratio greater than 1.