The bead portion of the pneumatic tire includes a bead structure having a bead core composed of bead cords, and an annular plate which is annular and extends to the tire circumferential direction and is formed of a resin material. The elastic modulus of the annular plate varies in tire radial direction.

A pneumatic tire includes: paired bead portions respectively including annular bead cores and bead fillers disposed on an outer side in a tire radial direction of the bead cores; sidewall portions respectively extending outward in the tire radial direction from the bead portions; a tread portion connected to cuter ends in the tire radial direction of the sidewall portions to form a tread; and a carcass layer suspended between the bead portions. The carcass layer has a first ply that continuously extends between the bead portions and that has opposite end portions respectively and a second ply that continuously extends on the outer side in the tire radial direction of the first ply, wherein the first ply has higher tensile strength than that of the second ply, and the end portion is positioned on the outer side in the tire radial direction of the end.

A pneumatic tire 1 has a carcass 6 extending between a first bead portion 4A and a second bead portion 4B through a tread portion 2 and a pair of sidewall portions 3. The carcass 6 is composed of at least two carcass plies 7 including a first carcass ply 7A and a second carcass ply 7B which have the same ply length. Each of the first carcass ply 7A and the second carcass ply 7B is arranged asymmetrically with respect to the tire equator C.

The bead portion of a pneumatic tire has a bead structure including a bead core having a bead cord covered with a resin material, and a bead filler continuous to the bead core and formed of the resin material and tapered outside in the tire radial direction. The bead structure has a weld line of the resin material. The weld line is formed inside in the tire radial direction more than ⅔ of the total height along the tire radial direction of the bead structure.

A pneumatic tire includes: paired bead portions respectively including annular bead cores and bead fillers disposed on an outer side in a tire radial direction of the bead cores; sidewall portions respectively extending outward in the tire radial direction from the bead portions; a tread portion connected to outer ends in the tire radial direction of the sidewall portions to form a tread; a carcass layer suspended between the bead portions; and a belt layer provided on an outer side in the tire radial direction of the carcass layer in the tread portion. The carcass layer has a first ply that continuously extends between the bead portions and that has opposite end portions and a second ply that extends from a position in contact with an inner peripheral face of an end portion, wherein the second ply has higher tensile strength than the tensile strength of the first ply.

A ply of a carcass of a pneumatic radial tire includes a turn-up ply and a down ply. The turn-up ply includes: a main body portion disposed between a pair of bead cores; turn-up portions around the bead cores from an inside toward an outside in a tire width direction. The down ply extends up to an inside in a radial direction of the bead cores so as to cover the turn-up ply including the turn-up portions from an outside. A curvature is formed at either one of a down ply predetermined portion of the down ply, which covers a turn-up end portion of the turn-up portion of the down ply from an outside in the tire width direction, and a turn-up ply portion that covers the turn-up end portion of the turn-up portion in the main body portion of the turn-up ply from inside in the tire width direction.

A run-flat tire includes a side reinforcing rubber layer, a first bead filler on an inner side of a carcass turned-up portion in a width direction, and a second bead filler on an outer side of the carcass turned-up portion in the width direction. A first bead filler height is 30% or less of a tire cross-sectional height SH. A second bead filler height is 50% or greater of the height SH. A cross-sectional area of the second bead filler is from 150% to 400% of a cross-sectional area of the first bead filler. A relationship (0.16×SH×LI−1100)≤S.sub.ALL≤(0.16×SH×LI−800) is satisfied, where S.sub.ALL represents a sum of cross-sectional areas of the side reinforcing rubber layer and the first and second bead fillers, and LI represents a load index.

The bead portion of a pneumatic tire has a bead structure including a bead core having a bead cord covered with a resin material, and a bead filler continuous to the bead core and formed of the resin material and tapered outside in the tire radial direction. The bead structure has a weld line of the resin material. The weld line is formed inside in the tire radial direction more than ⅔ of the total height along the tire radial direction of the bead structure.

A pneumatic tire has a rubber hardness higher than a rubber hardness of a rim cushion rubber, and includes a reinforced rubber between a turned back portion of a carcass layer and a sidewall rubber and between the turned back portion and the rim cushion rubber. A height H1 of a bead filler based on a measuring point of a rim diameter has a relationship of 0.10≤H1/SH≤0.23 with respect to a tire cross-sectional height SH. A height H2 of the reinforced rubber based on the measuring point of the rim diameter has a relationship of 0.40≤H2/SH≤0.55 with respect to the tire cross-sectional height SH. A cross-sectional area S2 of the reinforced rubber in a cross-sectional view in a tire meridian direction has a relationship of 1.10≤S2/S1≤2.70 with respect to a cross-sectional area S1 of the bead filler.

A pneumatic tire includes a tread portion, sidewall portions, a pair of bead portions embedded with bead cores, and a carcass. The carcass includes a turned up ply including a main body portion extending between the bead cores, and a pair of turned up portions turned up around the bead cores from axially inside to outside. Each bead portion is provided with an inner apex rubber extending radially outward from the bead core between the main body portion and the turned up portion and an outer apex rubber arranged axially outside the turned up portion. The inner apex rubber has a radial height of from 18 to 30 mm. A buttress thickness D, a maximum width thickness E, and a bead thickness F satisfy Expressions (1) to (4):

E≥4.5 mm  (1)

F≥9.0 mm  (2)

E/D=0.6 to 0.9  (3)

F/E=1.7 to 2.2  (4).