Abstract: A connecting piece interconnects the carburetor and combustion chamber of an internal combustion engine. The fuel-air mixture produced in the carburetor flows to the combustion chamber through the connecting piece in a primary flow direction. A plurality of closely spaced protrusions are provided on the inner wall of the connecting piece and these protrusions are disposed one behind the other and are offset from one another in the primary flow direction of the fuel-air mixture such that the formation of axially parallel channels is avoided. This embodiment prevents the fuel film deposited on the inner wall of the connecting piece from being completely aspirated all at once into the combustion chamber, which would cause a severe overenrichment of the mixture and hence a drop in rpm. Because of the many protrusions, the fuel film that is deposited tears off in the smallest possible pieces when being aspirated, so that only small parts of this film ever reach the combustion chamber at the same time.