Rotary wheel set system of a horological movement

A rotary wheel set system of a horological movement, the system comprising:

• a rotary wheel set;
• and
• a first and a second bearing, for a first and a second pivot of the arbor of the rotary wheel set,
• wherein the wheel set includes a mass center (G) in a position of its arbor,
• wherein the first bearing includes an endstone comprising a main body equipped with a conical cavity configured to receive the first pivot of the arbor of the rotary wheel set,
• wherein the first pivot being capable of cooperating with the cavity of the endstone in order to be able to rotate in the cavity, at least one contact zone between the first pivot and the cavity being generated, and
• wherein normals of the contact zone form a minimum contact angle (αh) relating to a plane perpendicular to the arbor of the first and second pivots, wherein the minimum contact angle (αh) is less than or equal to 30°.