An improved setting mechanism for a timepiece of a known type having a frame, a gear train, a detented setting stem rotatably mounted and axially slidable in the frame and having a toothed setting pinion which is engageable and disengageable with a plurality of crown teeth arranged on one of the gear train members, the stem setting pinion being arranged on a first axis and the crown tooth gear being arranged on a second axis. The improvement comprises offsetting the first axis so that it does not intersect the second axis and skewing the crown teeth in the direction of offset so that the setting pinion engages the crown teeth from a non-radial direction to facilitate engagement on only one side of the pinion. The offset further facilitates a stem extension in a non-interfering position.