Pneumatic tires for high speed vehicles

A pneumatic tire for high speed running vehicles comprising;

• a carcass composed of two plies of textile cords having an initial modulus of at least 100 g/denier, said cords being inclined to the equatorial plane of the tire at an angle from 20.degree. to 40.degree. and the cords of one of said plies being crossed with those of the other ply, a tread portion, a pair of bead portions each including bead wires around which is wound each end of said carcass to form a turn-up portion, an aspect ratio of 0.25 to 0.75 defined by H/W where H is the sectional height of the tire and W is the maximum sectional width of the tire, said cords of the carcass having a gap ratio in each ply (S.sub.1 /d).times.100 of 10% to 65% and a gap ratio between adjacent plies (S.sub.2 /d).times.100 of 22% to 83% where S.sub.1 is a distance between the cords in each ply, S.sub.2 is a distance between the cords in adjacent plies and d is a diameter of the cord, and wherein said cords of the carcass are embedded in a rubber layer having a modulus of elasticity of 300% elongation of 100 kg/cm.sup.2 to 250 kg/cm.sup.2, said turn-up portion having a top end located at a range of 30% to 80% of the sectional height of the tire, and a hard rubber filler interposed between said carcass plies including said turn-up portion.