Self-winding watch

A timepiece comprising a case and a self-winding mechanical horological movement comprising an oscillating weight rotably mounted on a portion of the horological movement, wherein a decorative disc is attached on the oscillating weight, said decorative disc being rotationally driven by said oscillating weight wherein the disc is free to move axially in relation to the weight in the direction perpendicular to the disc, so that the disc may be removed from the weight and wherein the back of the case is transparent so as to display the decorative disc, wherein:

• the movement comprises a pivoting shaft, the weight being fastened to or integral with the shaft,
• the disc is fastened to a support comprising a planar portion to which the disc is attached as well as a stem essentially perpendicular to the planar portion, the stem comprising at least one non-circular section portion,
• the shaft is provided with a central bore, also comprising at least one non-circular section portion, corresponding to the non-circular section of the portion of the stem,
• the non-circular section portion of the stem is inserted into the corresponding non-circular portion of the bore, so that the support and the disc are pivotally driven by the shaft.