In an inclined engine where a cylinder (2) projects from a crank case (1) obliquely and upwardly, when seen in a direction parallel to a center axis (3) of a crank shaft (10), under a specific observation condition in which the cylinder projecting direction is deemed as an upper right side, a valve operating cam gear (5) meshes with a crank gear (4) from a horizontal right side of the latter and a governor gear (6) is arranged in a space defined below a portion where the valve operating cam gear (5) meshes with the crank gear (4). This governor gear (6) engages with the valve operating cam gear (5) from a lower left side of the latter.