A variable valve timing system includes an exhaust swing arm swung in accordance with rotation of a camshaft, an intake swing arm similarly swung in accordance with the rotation of the camshaft, and a swing shaft swingably supporting the exhaust swing arm and the intake swing arm. In an engine including a plurality of the variable valve timing systems, the adjacent swing shafts are coupled to each other. The engine includes a link mechanism connected to one of the swing shafts, and an actuator for moving the link mechanism. The actuator controls turning angles of all the swing shafts via the link mechanism.