Patent ID: 8448683

Claim:
A heavy duty pneumatic tire comprising a tread portion, a pair of sidewall portions, a pair of bead portions each with a bead core therein, and a carcass ply of steel cords extending between the bead portions and turned up around the bead core in each said bead portion from the inside to the outside of the tire so as to form a pair of turned up portions and a main portion therebetween, wherein the steel cords of the carcass ply are rubberized with a topping rubber having a hardness Ht 1 of not less than 68 degrees but not more than 90 degrees, the bead core is composed of a bead core main made of windings of a steel wire, a rubber coating penetrating into the bead core main and having a hardness Hb of from 78 to 90 degrees, and a bead core wrapping layer surrounding the bead core main and composed of at least one ply of parallel organic fiber cords rubberized with a topping rubber having a hardness Ht 2 of from 70 to 90 degrees, wherein the fineness of each of said parallel organic fiber cords is in a range of from 940 to 4200 dtex, the distances between said parallel organic fiber cords is in a range of from 0.3 to 1.4 mm, said parallel organic fiber cords are inclined at an angle α 1 in a range of from 20 to 70 degrees with respect to the tire circumferential direction, and the hardness Ht 2 of the topping rubber of the bead core wrapping layer is greater than the hardness Ht 1 of the topping rubber of the carcass ply, but less than the hardness Hb of the rubber coating of the bead core, a minimum distance between the carcass cords and the axially innermost winding of the steel wire of the bead core main is in a range of from 0.8 to 3.0 mm, and said at least one ply is two plies in which, with respect to the tire circumferential direction, the organic fiber cords of one ply are inclined to one direction and the organic fiber cords of the other ply are inclined to the opposite direction thereto.