A rotary assembly , comprising: - an outer sub-assembly comprising a first annular outer raceway and a second annular outer raceway which are centered on a common axis of revolution ; - an inner sub-assembly comprising a first inner bearing ring on which a first inner raceway is formed, the first inner raceway having a raceway bottom diameter DI1, and a second inner bearing ring on which a second inner raceway is formed, the second inner raceway having a raceway bottom diameter DI2 larger than the raceway bottom diameter DI1 of the first inner raceway , the second inner bearing ring and the first inner bearing being fixed relative to each other; and - balls forming a first row of balls capable of rolling on the first outer raceway and the first inner raceway and a second row of balls capable of rolling on the second outer raceway and the second inner raceway for guiding the outer sub-assembly and the inner sub-assembly relative to each other in rotation about the axis of revolution , the balls of the first row of balls having a diameter DC1, a first pitch plane (PP1) containing the centers of the balls of the first row of balls being located at a non-zero distance L from a second pitch plane (PP2) containing the centers of the balls of the second row of balls; characterized in that: - the second inner bearing ring has an outer diameter (Φ), measured in a sectional plane (PC) perpendicular to the axis of revolution and located between the first pitch plane (PP1) and the second pitch plane (PP2), at a measurement distance DM from the first pitch plane (PP1), which is greater than a given threshold value VS, where: { DM = 1,25 × DC 1 2 VS = sup 1,1 × DI 1 ; DI 1 + DC 1 2 - an outer sub-assembly comprising a first annular outer raceway and a second annular outer raceway which are centered on a common axis of revolution ; - an inner sub-assembly comprising a first inner bearing ring on which a first inner raceway is formed, the first inner raceway having a raceway bottom diameter DI1, and a second inner bearing ring on which a second inner raceway is formed, the second inner raceway having a raceway bottom diameter DI2 larger than the raceway bottom diameter DI1 of the first inner raceway , the second inner bearing ring and the first inner bearing being fixed relative to each other; and - balls forming a first row of balls capable of rolling on the first outer raceway and the first inner raceway and a second row of balls capable of rolling on the second outer raceway and the second inner raceway for guiding the outer sub-assembly and the inner sub-assembly relative to each other in rotation about the axis of revolution , the balls of the first row of balls having a diameter DC1, a first pitch plane (PP1) containing the centers of the balls of the first row of balls being located at a non-zero distance L from a second pitch plane (PP2) containing the centers of the balls of the second row of balls; - the second inner bearing ring has an outer diameter (Φ), measured in a sectional plane (PC) perpendicular to the axis of revolution and located between the first pitch plane (PP1) and the second pitch plane (PP2), at a measurement distance DM from the first pitch plane (PP1), which is greater than a given threshold value VS, where: <EOS>