Patent ID: 7469731

Claim:
A heavy duty tire comprising a carcass extending from a tread portion to a bead core of a bead portion through a sidewall portion, and a belt layer disposed inside the tread portion and outside the carcass, the tread portion having two or more longitudinal main grooves extending continuously in a circumferential direction of the tire, wherein a shoulder groove of the longitudinal main grooves disposed at an outermost side in an axial direction of the tire has a groove center line passing through a region Y having (1) an inner boundary separated from a tire equator C by a distance of 0.4 times a half of the ground-contact width of the tread and (2) an outer boundary separated from the tire equator C by a distance of 0.7 times a half of the ground-contact width of the tread, in the profile line of the ground-contact surface shape when a normal load is applied to a tire in a normal internal pressure state in which the tire is mounted on the regular rim and a normal internal pressure is charged into the tire, an angle α formed between the axial direction of the tire and a straight line J 1 which passes through an equator point Pa on the tire equator and a groove-side edge point Pb on the tire equator side of the shoulder groove is set in a range of 5° to 12°, and an angle β formed by the axial direction of the tire and a straight line J 2 which passes through a groove-side edge point Pc on the tread ground-contact edge side of the shoulder groove and a ground-contact edge point Pd on a tread ground-contact edge is set in a range of not less than −3° but not more than the angle α, and the groove-side edge point Pc is located inside a straight line J 3 between the equator point Pa and the ground-contact edge point Pd, and the groove-side edge point Pb is located outside the line J 3 , and a tangent angle θ of a tangent X to the profile line with respect to the axial direction of the tire has a maximum value θmax in the region Y.