Abstract: This invention provides a pneumatic tire provided with a carcass (4) comprised of one or more carcass plies formed by covering plural reinforcing cords arranged in parallel with a coating rubber and a pair of side reinforcing rubber layers (5) each having a crescent shape in section and disposed at an inside of the carcass, wherein ride comfort during usual running and durability during run-flat running are improved by applying a cord including a polyketone fiber and satisfying conditions of equation (I): ???0.01×E+1.2 and equation (II): ??0.02 [wherein ? is a heat shrinkage stress (cN/dtex) at 177° C. and E is an elastic modulus (cN/dtex) at 25° C. under a load of 49 N] to the reinforcing cord and a rubber composition having a loss tangent (tan ?) at 25° C. and 1% strain of less than 0.12 and a viscosity (G?) at 130° C. during unvulcanization of not less than 50 MPa to the coating rubber.

Abstract: This invention provides a pneumatic tire provided with a carcass (4) comprised of one or more carcass plies formed by covering plural reinforcing cords arranged in parallel with a coating rubber and a pair of side reinforcing rubber layers (5) each having a crescent shape in section and disposed at an inside of the carcass, wherein ride comfort during usual running and durability during run-flat running are improved by applying a cord including a polyketone fiber and satisfying conditions of equation (I): ???0.01×E+1.2 and equation (II): ??0.02 [wherein ? is a heat shrinkage stress (cN/dtex) at 177° C. and E is an elastic modulus (cN/dtex) at 25° C. under a load of 49 N] to the reinforcing cord and a rubber composition having a loss tangent (tan ?) at 25° C. and 1% strain of less than 0.12 and a viscosity (G?) at 130° C. during unvulcanization of not less than 50 MPa to the coating rubber.

Abstract: This invention relates to a pneumatic tire comprising a pair of bead portions (1), a pair of sidewall portions (2), a tread portion (3) continuing to both the sidewall portions (2), a carcass (4) composed of one or more carcass plies toroidally extending between the pair of bead portions and reinforcing these potions and a pair of side reinforcing rubber layers (5) each disposed on an inside of the carcass (4) at the sidewall portion (2), wherein the carcass ply is formed by covering reinforcing cords with a coating rubber and a rubber composition having a loss tangent (tan ?) at 25° C. and 1% strain of not higher than 0.12 is applied to the coating rubber, and/or a rubber composition having a loss tangent (tan ?) at 25° C and 1% strain of not higher than 0.15 is applied to the sidewall portion (2).