Patent ID: 7472735

Claim:
A pneumatic radial tire comprising a carcass structure, a belt stucture, and a tread, wherein the belt structure is comprised of at least three plies of reinforcing cords, the cords in the at least three plies being inclined at angles greater than 5% relative to a centerline of the tire, the tire being characterized by having a stiffness variation in the circumferential and meridional directions of the at least three belt plies wherein a first radially innermost ply has a first stiffness, a second radially itermediate ply has a second stiffness, and a third radially outermost ply has a third stiffness, the first stiffness being greater than the second stiffness and the second stiffness being greater than the third stiffness, and a difference between the first stiffness and second stiffness being greater than a difference between the second stiffness and the third stiffness, a stiffness variation between the first stiffness and the third stiffness being in the range of 12 to 25%.