Steel radial tire

A steel radial tire comprising:

• a tire tread;
• a tire belt located in a radially inward direction of the tire tread;
• a tire carcass located in a radially inward direction of the tire belt, and having a plurality of steel cords embedded in a quantity of rubber;
• each of the steel cords comprising three first wires positioned to form a core strand, each of the three first wires having a first diameter;
• nine second wires, respectively having a second diameter smaller than said first diameter of said first wires, positioned to enclose said first wires in said core strand, the second wires being twisted together with the three first wires in a same direction, said first diameter being 5 percent to 15 percent greater than the second diameter, the second wires having a space S2 therebetween, the space S2 being defined as a space having a shortest distance between a respective outer surface of each of two adjacent second wires, and the space S2 being 10 percent to 25 percent of a sum of a diameter of one of the second wires and the space S2;
• a plurality of third wires positioned to enclose the second wires, the third wires being twisted in a direction opposite to the same twisting direction of the first and second wires;
• and
• a space S1 between adjacent ones of the third wires, said quantity of rubber sufficiently entering the spaces S1 and S2 to achieve a strong bonding between the three first wires and the nine second wires such that the three first wires will not be pulled out while the tire is running.