As to a reciprocating stroke wiper system for motor vehicles with a piston movably guided in a housing a projecting arm unrotatably fixed to the piston and comprising a guiding fork is provided as a protection against twisting, which projecting arm is guided along a guiding element fixed to the housing. According to the invention a rod with circular cross-section is used as a guiding element, which rod is arranged at an angle towards the axis of the piston so that the guiding areas of the guiding rod and of the guiding fork touching each other are displaced crosswise to them during the motion so that the effective guiding area is enlarged and thus wear is reduced.