What transfers valve train motion to valve stem tips?

The valve train motion is transferred to the valve stem tips primarily through rocker arms. These components pivot on a shaft or fulcrum and are activated by pushrods or directly by cam lobes in overhead camshaft designs. As the cam rotates, it pushes the rocker arm, which in turn pushes down on the valve stem, opening or closing the valve as needed. This mechanical linkage ensures precise timing and movement of the engine's intake and exhaust valves.