Abstract: A tyre comprises a casing ply having a meridian profile with a central crown portion and two sidewall portions; in the inflated configuration of the tyre, the crown profile portion has a radius of meridian curvature &rgr;c in the range from 406 mm to 690 mm and each sidewall profile portion forms an angle &agr;s with the axis of rotation of the tyre in the range from 25° to 30°; additionally, a mould for a tyre has cheek profiles which have a first and a second radius of curvature Rfs/Rfi whose ratio Rfs/Rfi ranges from 0.45 to 0.56 and a base profile of one sector having a radius of meridian curvature R≧500 mm and a shoulder angle &agr;0≧42°.

Abstract: A mould for producing a tire includes a crown and at least two cheeks. The crown includes radially-movable sectors. A first cheek is axially opposite a second cheek. The mould includes a main profile in a plane of a meridian section. The main profile includes a maximum chord, a maximum height measured from a fitting line, a profile of the first and second cheeks, and a base profile of a sector. The base profile includes first and second lateral portions, first and second connecting portions, and a central portion. The first lateral and connecting portions are axially opposite the second lateral and connecting portions. Each cheek profile includes first and second portions including first and second radii of curvature, where a ratio of the first radius of curvature to the second radius of curvature is greater than or equal to 0.45:1 and less than or equal to 0.56:1.