Furthermore, as the side wall rubber 17, relatively soft rubber with {HEAD ~ 100% modulus} of {TAIL ~ 14 to 50 kg}/cm2 is used, and the side packing rubber 15 with 100% modulus of 53 to 95 kg/cm2, being smaller than that of the bead apex rubber 9 and greater than that of the side wall rubber 17 is provided between them 