A radial tire having at least one side wall and a carcass reinforcement consisting of at least one ply (20) reinforced by parallel threads (24) in substantially radial direction, termed radial threads, and having at least one lap weld (21) formed by superposition of two ends (22, 23) or adjacent elements of said ply, characterized in that, in the side wall, the general orientation (D2) of the lap weld is oblique with respect to the direction (D1) of the radial threads (24). The radial tire for a passenger vehicle or van, has a carcass reinforcement which includes a single radial ply, the radial threads (24) having in particular a polyester, particularly polyethylene terephthalate base. The tire according to the invention, compared to prior art radial tires, presents an improved outward appearance of the side walls.