A printing group of a rotary printing press, - with at least one cylinder, especially a printing cylinder, - with a rotatable drive shaft, by which a torque can be provided, and - with which transmission means are provided between drive shaft and the cylinder, with which torque can be transmitted from the drive shaft to the cylinder and which can be detached from the cylinder and/or from the drive shaft, characterized in - that the transmission means comprise at least one connection piece and at least one counter-piece, wherein the one of said pieces (11, 21) comprises an inclined surface (18, 22) and the other of said pieces comprises edges or surfaces (22, 18), which come into contact with the inclined surface (18, 22), - that means (24, 25, 26) are provided for the relative displacement of the connection piece and the counter-piece towards each other, wherein as a result of the displacement the edges and/or surfaces (18, 22) coming into contact can be subjected to variable forces, such that the inner or outer diameter of the connection piece or of the counter-piece can be modified and - that a locking pin is provided, which can be applied to a wall arranged on the counter-piece, on the connection piece or on the sleeve, wherein the locking pin can be moved relative to the wall by means of piston cylinder unit fixed to the frame. - with at least one cylinder, especially a printing cylinder, - with a rotatable drive shaft, by which a torque can be provided, and - with which transmission means are provided between drive shaft and the cylinder, with which torque can be transmitted from the drive shaft to the cylinder and which can be detached from the cylinder and/or from the drive shaft, characterized in - that the transmission means comprise at least one connection piece and at least one counter-piece, wherein the one of said pieces (11, 21) comprises an inclined surface (18, 22) and the other of said pieces comprises edges or surfaces (22, 18), which come into contact with the inclined surface (18, 22), - that means (24, 25, 26) are provided for the relative displacement of the connection piece and the counter-piece towards each other, wherein as a result of the displacement the edges and/or surfaces (18, 22) coming into contact can be subjected to variable forces, such that the inner or outer diameter of the connection piece or of the counter-piece can be modified and - that a locking pin is provided, which can be applied to a wall arranged on the counter-piece, on the connection piece or on the sleeve, wherein the locking pin can be moved relative to the wall by means of piston cylinder unit fixed to the frame. - with which transmission means are provided between drive shaft and the cylinder, with which torque can be transmitted from the drive shaft to the cylinder and which can be detached from the cylinder and/or from the drive shaft, characterized in - that the transmission means comprise at least one connection piece and at least one counter-piece, wherein the one of said pieces (11, 21) comprises an inclined surface (18, 22) and the other of said pieces comprises edges or surfaces (22, 18), which come into contact with the inclined surface (18, 22), - that means (24, 25, 26) are provided for the relative displacement of the connection piece and the counter-piece towards each other, wherein as a result of the displacement the edges and/or surfaces (18, 22) coming into contact can be subjected to variable forces, such that the inner or outer diameter of the connection piece or of the counter-piece can be modified and - that a locking pin is provided, which can be applied to a wall arranged on the counter-piece, on the connection piece or on the sleeve, wherein the locking pin can be moved relative to the wall by means of piston cylinder unit fixed to the frame.