A front derailleur actuation device having a cable-winding bush in a casing rotatable about axis (X) in a first angular direction (A) between a first angular position and a last two angular positions to actuate a member mounted rotatable about axis (X) and a stationary member mounted in the casing. Either the rotating member or the stationary member is provided with at least one pointer slidably engaged on a fastening track equipped with a plurality of stop areas provided on the other member. The stationary member or the rotating member provided with the fastening track further comprises at least one further stop area not arranged along the fastening track, said further stop area being engageable by the pointer and being arranged between two successive stop areas of said fastening track, the cable-winding bush passing between two angular positions following the passage of the pointer between two stop areas.