A wheel adapter for fastening on a wheel, in particular on a wheel of a motor vehicle, includes at least two arms which extend in a radial direction starting from a central area of the wheel adapter Each of the arms includes at least one movable element which is movable in the radial direction in order to vary the length of the arm in the radial direction. The movable elements of at least two arms are mechanically coupled to one another in such a way that a movement of one movable element of a first arm results in a corresponding movement of a least one movable element of a second arm.