A dry-sump lubrication type four-stroke cycle engine having a crankcase provided with a crankshaft chamber in its front part and a transmission chamber in its rear part, a generator chamber on one side of the crankcase in an axial direction of the crankshaft, and a clutch chamber on the other side of the crankcase. The engine driven generator further includes a power source and a circuit connecting the power source to the first electrical fan and the second electrical fan. The second end comprises at least one recess extending from a side of the connector.