Gear mechanism (1) having a toothing (5), a tooth carrier (11) accommodating a plurality of teeth (7) for engagement with the toothing, the teeth (7) being radially displaceable relative to the tooth carrier (11), a drive input with a profiling (22) for radially driving the teeth (7), and bearing segments (24) for mounting the teeth on the profiling. Each bearing segment includes a running side oriented in the direction of the profiling and a bearing side opposite the running side, a tooth bearing arranged on the bearing side for articulated mounting of at least one of the teeth, the tooth bearing including a bead which is at least substantially in the shape of a cylinder section and arranged from a first side edge to a second side edge of the bearing segment transverse to a running direction of the bearing segment. The bead is in a central region between the first and second side edges and has a first and/or second recess on a first and/or second side of the central region.