In a pneumatic tire in which a side reinforcing layer having a crescent-shaped cross-section is provided on an inner side in a tire width direction of a carcass layer in a sidewall portion, organic fiber cords having an elongation of 4.3% to 6.0% under a 1.5 cN/dtex load and a total fineness of 4000 dtex to 6000 dtex are used as carcass cords constituting the carcass layer.

A pneumatic tire includes a longitudinal protrusion portion provided on at least one of tire side surfaces located on either side in a tire lateral direction, the longitudinal protrusion portion projecting from the tire side surface and extending along the tire side surface; and serration provided on the tire side surface in a region including an end portion of the longitudinal protrusion portion, the serration being formed of a plurality of small grooves arranged in parallel, and the plurality of small grooves being inclined with respect to a lateral centerline that passes through a center of the longitudinal protrusion portion in a width direction.

A pneumatic tire includes a run-flat reinforcing layer disposed on an inner side in a width direction of a carcass layer, and a second filler disposed between a turned back portion of the carcass layer and a rim cushion rubber. Additionally, a point on a tire outer circumferential surface is defined, the point is located at a position corresponding to 150% of a rim flange height from a measurement point of a rim diameter of a specified rim, a perpendicular line is defined, and the perpendicular line is drawn from the point to a tire inner circumferential surface. A rubber gauge (G1) of the run-flat reinforcing layer on the perpendicular line, and a rubber gauge (G2) of a region from the turned back portion of the carcass layer to a tire outer surface have the relationship 0<G1/G2≤0.65.

A run-flat tire has a belt-end reinforcing layer provided between the tread portion and a width outside end of the belt layer, and formed of a resin material. The belt-end reinforcing layer is annular along a tire circumferential direction, has a predetermined width along the tire width direction, and is provided in the tire width direction so as to cover a radial outside end of a side reinforcing rubber and a width outside end of the belt layer.

A run-flat tire is provided with a belt layer having a circumferential cord extending along the tire circumferential direction covered with a resin material, a first resin reinforcing layer provided on the outside of the belt layer of the tire radial direction and formed of a resin material, and a second resin reinforcing layer provided on the inside of the belt layer of the tire radial direction and formed of a resin material, wherein the first resin reinforcing layer and the second resin reinforcing layer have a predetermined width along the tire width direction and are provided so as to sandwich the tire radial direction outside end of a side reinforcing rubber from the outside of the tire radial direction and the inside of the tire radial direction.

Provided is a run-flat tire having improved durability performance during travel while the tire is running flat. A surface section of a sidewall of the run-flat tire is provided with an uneven section. A sidewall reinforcement layer is configured such that a breaking strength TB (MPa) at 100° C.×an elongation at break EB (%) is 320 or more and a loss tangent 100° C. tan δ at 100° C. is 0.06 or less, and the sidewall is configured such that a loss tangent 60° C. tan δ at 60° C. is 0.17 or less and |60° C. tan δ−75° C. tan δ| is less than 0.05.

A pneumatic radial tire includes a carcass structure having a pair of sidewalls and a crown, a pair of beads, a tread, a belt structure, and a plurality of reinforcing hoops. The plurality of spaced apart reinforcing hoops are disposed intermediate the crown of the carcass structure and the tread, and are formed of a rigid material coated in an elastomeric material. The plurality of reinforcing hoops includes a pair of outer reinforcing hoops disposed adjacent the sidewalls of the carcass, and an at least one inner reinforcing hoop disposed between the outer reinforcing hoops.

At a run-flat tire, given that an average radius of curvature of a case line between an intersection point (0.1 SHp) and an intersection point (0.2 SHp) when viewed in a cross-section along a tire rotation axis is radius R1, and that an average radius of curvature of the case line between an intersection point (0.4 SHp) and an intersection point (0.6 SHp) when viewed in the cross-section along the tire rotation axis is radius R2, ratio R2/R1 is set to be greater than 0.3.

A pneumatic tire is provided. In a meridian cross-section, an external contour shape of the bead core is a polygon formed by common tangent lines of a plurality of circumferential portions of a bead wire, the external contour shape includes a single vertex located toward the outside in a tire radial direction, an internal angle formed by two sides sandwiching the vertex is an acute angle, a bottom side of the external contour shape is inclined with respect to the tire lateral direction by from 2° to 9°, and the carcass layer is bent and folded back along a circumference of the bead core in a bead portion, a folded back portion of the carcass layer from a position of an outer end of the bead core in the tire radial direction extends toward a sidewall portion in contact with a body portion.

In a cross-section of a pneumatic tire, a contour of the bead core is a polygon formed by tangent lines of circumferential portions of a bead wire, the contour includes a vertex with an acute angle and a bottom side opposite the vertex, the carcass layer is folded back along a circumference of the bead core in a bead portion, a folded back portion of the carcass layer from an outer end of the bead core extends in the radial direction, and a distance in the radial direction between a center of an arc profile of a tire outer surface and a straight line extending in the lateral direction through the vertex is within 20% of a radius r of the arc, and a distance in the lateral direction between the center of the arc and a straight line extending in the radial direction through the vertex is within 2r±0.4r.