Rim, supporting ring and assembly thereof

An integral rim for a tire having at least two beads, the rim comprising, when viewed in meridian section, a first rim edge and a second rim edge spaced apart axially by the rim width S, a first rim seat, a second rim seat and a rim base between the rim seats, the first and second rim seats each having inner and outer ends, the inner ends being more remote from the corresponding rim edge, the first rim seat having a generatrix with axially inner and outer ends, the axially inner and outer ends of the generatrix of the first rim seat being on circles of different diameter, the diameter of the circle of the axially inner end being greater than the diameter of the circle of the axially outer end, a hump on the outer end of the first rim seat, the second rim seat having a generatrix having axially inner and outer ends, the axially inner end of the generatrix of the second rim seat being on a circle of diameter greater than or equal to the diameter of the circle on which the axially inner end of the first rim seat is located, and the rim base, being without a mounting groove and having a minimum diameter, which is the diameter of its end which is axially closest to the first rim seat, equal to or greater than the diameter of any part of the rim included between said end and the first rim edge.