A non-normalised section of the wheel has at least one curve (9) stretching radially over the whole circumference and stiffening the wheel rim (1). The centre axis of the curve coincides with the rim axis and is located outside the normal rim profile (22). The curve is orientated radially inwards and is located in the ledge area. The rim may have two curves lying next to each other, and a curve may be located in the well base area and orientated radially outwards.
