Radial tire for heavy load vehicles

In a radial tire for heavy load vehicles constructed to effectively suppress wandering phenomenon having a pair of annular bead bundles, a radial carcass toroidally extending across said bead bundles, and a tread portion including a reinforcing belt superimposed about said radial carcass, said tread portion having an outer contour composed of a relatively transversely flat main region exclusively adapted to make contact with ground when the tire runs normally and a conical region located at both end edges of said main region and inclined at an given angle of 30.degree.-60.degree. with respect to a tangent drawn from the tread in parallel with the rotary axis of the tire, the improvement comprising;

• a number of thin incisions extending across said conical region and having inner ends each located on at least the outer surface of the tread at a portion not reaching the inside of said main region, said incisions being circumferentially spaced apart from each other by a distance which is within a range between 1% and 5% of the width of the main region of the tread portion, said conical region having a width measured in a direction parallel to the rotary axis of the tire and lying within a range between 2% and 7% of the width of said main region and said incisions having a gap within a range between 0.3 mm and 1 mm.