PNEUMATIC RADIAL TYRE

PURPOSE:To improve appearance and renewing ability prevailing during the final stage of wear, by a method wherein, in a heavy load tyre for buss and the like, a belt layer is formed with a main belt layer, wherein a metallic cord is used, and an auxiliary belt layer where cord selected from boron fibre, silicon carbide fibre is used. CONSTITUTION:A belt layer 5 is formed with a main belt layer 6 and an auxilia ry belt layer 7 located outside the main belt layer. The main belt layer 6 is formed by two main plies 6a, formed such that rubber-covered metallic cord is arranged at an angle of 30 deg. or less with the circumferential direction of a tyre, and a main ply 6b formed such that the cord is arranged at an angle of 70 deg. with the circumferential direction. An auxiliary belt layer 7 is formed by covering with rubber high strength fibre selected from boron fibre and silicon carbide fibre, and by two or less auxiliary plies 7a having maximum width W7 being 35-75% of a maximum width W6 of the main belt layer 6. This constitution improves durability of the belt layer and enables improvement of appearance and renewing ability prevailing during the final stage of wear.