A two-stroke engine has a piston, mounted to be displaced in a cylinder, connected by means of a connecting rod to a crankshaft mounted to rotate about an axis in a crankcase that defines a crankcase chamber. The crankshaft includes a crankshaft duct that opens into the crankcase chamber which is, depending on the angle of rotation of the crankshaft, connected by way of an inlet opening in the crankshaft to an inlet manifold for an air/fuel mixture. The cylinder includes a transfer port, by way of which, the air/fuel mixture flows from the crankcase chamber past the piston into the working chamber based on the position of the piston in the cylinder. An increase in engine power is achieved by a gas mixing duct, a slot or a deflecting element arranged within the crankcase which improve(s) the filling of the crankcase chamber with the air/fuel mixture.