Mechanical horological movement with power reserve detection

A mechanical horological movement (1) including at least one barrel system (2) for driving a set of wheels and power reserve detector. The detector (10) includes a control wheel (3) disposed opposite the cage of the barrel system (2) and is rotated by a complementary wheel (8) at the differential output to determine a power reserve level. An aperture (13) has a first end (21) to define a complete charge of the barrel system and a second end (22) to define a complete discharge. A lever (4) is rotatably mounted about a lever axis parallel to the axis of rotation of the control wheel. A contact element (5) disposed in the aperture contacts the second end during a zero power reserve indication. A portion of the lever contacts a component of the movement to stop its operation when power reserve indication is at zero.