A rear wheel (3) is mounted on a bicycle frame. A first
spoke (11) has a first bore (110), and a second
spoke (12) has a first threaded bore (120) coaxial with the first bore (110) and a third axial
bearing surface (121) on the inside of the second
spoke (12). The rear wheel (3) consists of a wheel hub (31) and a cassette of sprockets (2) equipped with a first pair of
interlocking surfaces (6) that provide a rotational and coaxial engagement position for the wheel hub (31) with the cassette of sprockets (2) in the wheel-mounted position on the frame, and a disengagement position for the wheel hub (31) to remove it, while the cassette of sprockets (2) remains on the second spoke (12) of the frame. The wheel hub (31) rotatably supports a first hollow axle (32).The cassette
assembly of sprockets (2) rotatably supports a cassette-carrying sleeve (20) which has a threaded tenon (201) screwed into the tapped hole (120), a fourth axial
bearing surface (202) which abuts against the third axial
bearing surface (121), and a second tapped bore (204) coaxial with the threaded tenon (201) into which a threaded end (342) of a fixing pin (34) is screwed. A safety device (22) ensures that the cassette-carrying sleeve (20) does not unscrew during tightening or loosening of the fixing pin (34). [Fig 2].