PURPOSE: To improve the hot starting performance by controlling variable the timing of a suction valve and an exhaust valve responding to the rotation frequency of the engine, and increasing the time area of overlapping the suction and the exhaust valves in a hot starting time.
CONSTITUTION: The timing of a suction valve and an exhaust valve in an engine is set variable by using a variable mechanism 30. And the rotation frequency of the engine is detected by a detecting means 22. Furthermore, the variable mechanism 30 is controlled by a control means 81 to make the timing of the suction valve and the exhaust valve into a timing responding to the engine rotation frequency. And in a hot starting of the engine, the control of the variable mechanism 30 by the control means 81 is corrected by a correcting means 82 so as to increase the time area of overlapping the suction and the exhaust valves. As a result, the scavenging efficiency in the overlapping period of the suction and the exhaust valves is improved in a hot starting time so as to suppress a smoking of the ignition plug, and a poor starting can be prevented.
ENDO KOJI
YOSHIDA SEIJI
