摘要 |
A high-speed running pneumatic radial tire comprises a cylindrical crown portion, a pair of sidewall portions extending inward therefrom, a radial carcaas (7) extending from one of the sidewall portions through the crown portion to the other sidewall portion, and a belt (8) and a tread (9) successively superimposed on the crown portion outward in the radial direction of the tire. The tread has a plurality of rows of blocks (3) defined by a plurality of circumferential grooves (1a,1b) and by lateral grooves (2a,2b), and the belt (8) is comprised of at least two main cross-cord belt layers (8a) and an auxiliary belt layer (8b) arranged thereon. The auxiliary belt layer is formed by spirally winding a rubberized ribbon ply of heat-shrinkable cords (12) on the main belt layers (8a), in which an overlapped amount of the ribbon ply is made larger in a zone (B,C) of the tread substantially corresponding to a block row (3) than in a zone (A) of the tread substantially corresponding to a circumferential groove (1a,1b). <IMAGE> |