An internal combustion engine has one or more engine cylinders (12) within which fuel is combusted and a pair of cylinder valves (14, 16) spring-biased (22, 24) closed but open in unison to place the respective cylinder in flow communication with one of an intake and an exhaust. A bridge (34) bridges ends of the pair external to the cylinder and has a spherically concave depression (42) in a face that is opposite a face that bears against the ends of the pair. The depression is located intermediate locations at which the ends of the pair bear against the bridge. A pivot foot (44) has a spherically convex surface (46) seated with substantial conformity in the depression and a flat surface (48) opposite the spherically convex surface. The flat surface of the pivot foot abuts a flat surface (50) of a rocker (30) that when rocked acts through the pivot foot and bridge to open the respective pair of valves.