| 摘要 |
PROBLEM TO BE SOLVED: To provide a pneumatic radial tire having various improved characteristics on a high level such as maneuvering stability, riding quality against vibration, the side appearance of a tire, and uniformity. SOLUTION: In a pneumatic radial tire having a carcass 2 comprising at least one of plies formed by radially disposing cords between a pair of beads 1 as a skeleton, the carcass is an annulus body comprising plies formed by rubberizing a large number of polyester fiber cords and having no overlapping joint of the cords in the circumferential direction of the tire, the intermediate percentage of elongation of the polyester fiber cord under a loaded condition and the percentage of dry heat contraction under a loaded condition are numerically restricted, and the bead core is structured by laminating layers formed by spirally winding a rubber coated wire having a restricted diameter side by side and one by one on the outside in its radius direction, by restricting a distance between the axial centers of adjacent wires in a cross section in a tire width direction, and by having one more wire arranged side by side in a second layer on the furthest inside than those in a first layer.
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