Rotor system for a bicycle for the bearing of a fork and for the transmission of actuations of Bowden cables (31, 32) each having a core (31a, 32a), with at least a first and a second transmission element (36, 37) which are rotatable relative to one another and which are arranged in the area of the bearing (21, 23, 25) of the fork, wherein - the transmission elements (36, 37) have at least a ring-shaped area, which is mounted on the fork steerer of the fork and is surrounded by a head tube at least in radial direction, - the core of a first Bowden cable of the provided Bowden cables (31, 32, 33) is connected with the first transmission element, - the core of a second Bowden cable of the provided Bowden cables (31, 32, 33) is connected with the second transmission element, - the transmission elements (36, 37) have connection areas (36b; 37b) for the direct or indirect attachment of the rotor side ends of the cores (31a 32a), and - the second transmission element comprises a connection area arranged inside the head tube, at which connection area a connecting element is form-fittingly attachable aid-free, wherein the connecting element interacts detachably with the rotor side end of the core assigned to the second transmission element, or is connected in one piece to it, characterised in, that - the core of the first Bowden cable extends at least sectionally in the fork steerer, - at the rotor side end of the core, a bar is provided that protrudes through oblong-hole-shaped fork steerer openings in radial direction beyond the outer circumference of the fork steerer, and the ends of which are received by the first transmission element, and - the bar during installation, when introduced into the fork steerer, is tiltable relatively to the core of the first Bowden cable. - the transmission elements (36, 37) have at least a ring-shaped area, which is mounted on the fork steerer of the fork and is surrounded by a head tube at least in radial direction, - the core of a first Bowden cable of the provided Bowden cables (31, 32, 33) is connected with the first transmission element, - the core of a second Bowden cable of the provided Bowden cables (31, 32, 33) is connected with the second transmission element, - the transmission elements (36, 37) have connection areas (36b; 37b) for the direct or indirect attachment of the rotor side ends of the cores (31a 32a), and - the second transmission element comprises a connection area arranged inside the head tube, at which connection area a connecting element is form-fittingly attachable aid-free, wherein the connecting element interacts detachably with the rotor side end of the core assigned to the second transmission element, or is connected in one piece to it, - the core of the first Bowden cable extends at least sectionally in the fork steerer, - at the rotor side end of the core, a bar is provided that protrudes through oblong-hole-shaped fork steerer openings in radial direction beyond the outer circumference of the fork steerer, and the ends of which are received by the first transmission element, and - the bar during installation, when introduced into the fork steerer, is tiltable relatively to the core of the first Bowden cable.