Incremental measuring path system for a bicycle, for determining a rotational speed of a wheel of the bicycle relative to a fixed point on the bicycle, for example a fork and/or a frame, comprising at least one signal transmitter means with a plurality of signal transmitters, and at least one sensor element cooperating with these signal transmitters, wherein the signal transmitter means can be arranged on the wheel and the sensor element can be arranged on the fixed point, or vice versa, in such a way that, during a rotation of the wheel, the signal transmitters rotate past the sensor element in order to scan at least one signal path (214, 218) and form at least one tappable measurement signal, wherein the signal transmitters are arranged in a signal transmitter plane (Es), and at least one of the signal transmitters, optionally exactly one of the signal transmitters, is designed as a calibration element comprising at least one signal path which is designed differently from the signal paths of the other signal transmitters, wherein each signal transmitter has a leading edge and a trailing edge, wherein the leading edge defines the beginning of the signal path (214; 218) and the trailing edge defines the end of the signal path (214; 218) of the signal transmitter, wherein each signal transmitter is opaque in the region of its signal path between the leading edge and the trailing edge, wherein the signal transmitters are arranged on a signal transmitter base comprising an axis (Ax) which can be arranged to be coaxial with the axis of rotation of the wheel, and wherein the signal path of the calibration element is shorter or longer than the signal paths of the other signal transmitters, characterized in that the trailing edge of each individual signal transmitter is spaced apart from the leading edge of the signal transmitter following it in a circumferential direction of the signal transmitter base in the circumferential direction of the signal transmitter base, so that all individual signal generators are spaced apart from each other in the circumferential direction of the signal transmitter base, wherein, from the detection of the signal path of the calibration element by the sensor element, a reliable conclusion can be reached about the actual rotational speed of the wheel and this results in a secure protection against manipulation. the signal transmitters are arranged in a signal transmitter plane (Es), and at least one of the signal transmitters, optionally exactly one of the signal transmitters, is designed as a calibration element comprising at least one signal path which is designed differently from the signal paths of the other signal transmitters, wherein each signal transmitter has a leading edge and a trailing edge, wherein the leading edge defines the beginning of the signal path (214; 218) and the trailing edge defines the end of the signal path (214; 218) of the signal transmitter, wherein each signal transmitter is opaque in the region of its signal path between the leading edge and the trailing edge, wherein the signal transmitters are arranged on a signal transmitter base comprising an axis (Ax) which can be arranged to be coaxial with the axis of rotation of the wheel, and wherein the signal path of the calibration element is shorter or longer than the signal paths of the other signal transmitters, characterized in that the trailing edge of each individual signal transmitter is spaced apart from the leading edge of the signal transmitter following it in a circumferential direction of the signal transmitter base in the circumferential direction of the signal transmitter base, so that all individual signal generators are spaced apart from each other in the circumferential direction of the signal transmitter base, wherein, from the detection of the signal path of the calibration element by the sensor element, a reliable conclusion can be reached about the actual rotational speed of the wheel and this results in a secure protection against manipulation.