A two stroke combustion engine comprising at least one combustion cylinder (13) having a cylinder center axis (19), a combustion piston (12) movable within the combustion cylinder (13), the combustion piston (12) having a first compression direction (CD) along the cylinder center axis (19). The two stroke combustion engine further comprising at least one separate piston pump (3a) having a piston pump cylinder (3b) with a piston pump center axis (20b) and a pump piston (25) movable within the piston pump cylinder (3b). The separate piston pump (3a) is in movable mechanical connection (18) with the combustion piston (12). The two stroke combustion engine further comprising an air inlet (10) having an air inlet center axis (20a). The separate piston pump (3a), the air inlet (10) and the combustion cylinder (13) are in fluid connection with each other by a transfer channel (11), and the piston pump center axis (20b) intersects a cylinder plane (X-19) extending from the cylinder center axis (19), and the intersection defines a ray (19') extending from the intersection in the first compression direction (CD). A normal axis (N) extends perpendicularly from the cylinder plane (X-19), the normal axis (N) intersects the piston pump center axis (20b). An angle, measured from the intersection between the ray (19') and a point on the piston pump center axis (20b), located in the piston pump cylinder (3b), is between 30° and 160°.