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.

This invention relates to pneumatic radial tires which exhibit improved rolling resistance (provide better fuel economy) and improved performance characteristics. More particularly, this invention relates to the structure of radial ply tires for heavy load vehicles such as trucks, buses, and the like. It is based upon that finding that a defined profile of the outer surface of the sidewall portion can lead to a tire with reduced rolling resistance and a reduced generation of heat. The reduction in rolling resistance is obtained by a specific shaping of the bead portion of the tire which allows a bead mass reduction with an acceptable trade-off with regard to bead durability.

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.

In a tire 22, a length from a center PM in an axial direction of a boundary 60 between a core 48 and an apex 50 to an outer edge PA of the apex 50 is not less than 10 mm and not greater than 15 mm. In a state where the tire 22 is mounted on a normal rim and an internal pressure of the tire 22 is adjusted to 10% of a normal internal pressure, a main body portion 54 of a carcass ply 52 extending along an inner surface 62 of the apex 50 is tilted relative to the axial direction, and an angle of the main body portion 54 relative to the axial direction is not less than 40° and not greater than 60°.

The method is a method of manufacturing a tire, the tire-including bead cores, a bead filler-extending outward in a tire radial direction of each of the bead cores, a carcass ply extending from one bead core—to another bead core—and folded back around the bead cores, and an electronic component, the method comprising: a covering step of covering the electronic component with coated rubber; a recess forming step of forming, in the bead filler, a recess-having a shape corresponding to a shape of the coated rubber; and a disposing step of disposing the coated rubber, which at least partially covers the electronic component, in the recess-in the bead filler.

A tire for a two-wheeled automotive vehicle includes a carcass that is extended on and between one of beads and the other of the beads along inner sides of a tread and sidewalls. The carcass includes a first ply and a second ply that is layered outward of the first ply. The first ply is turned up around the beads from an inner side toward an outer side in an axial direction. By the turning-up, the first ply includes a main portion and turned-up portions. The second ply is turned back around the beads from the outer side toward the inner side in the axial direction. By the turning-back, the second ply includes a main portion and turned-back portions.

A pneumatic tire comprises a tread portion, sidewall portions, bead portions each with a bead core embedded therein, and a carcass extending between the bead portions and comprising first carcass cords and second carcass cords. The first carcass cord comprises: a main portion extending from the tread portion to the bead portions via the sidewall portions; and folded-back portions continued from the main portion and folded back around the bead cores from the inside to the outside in the tire axial direction. The second carcass cord extends from the tread portion to the bead portions and terminates on the axially outside of the folded-back portions of the first carcass cords. Young's modulus of the second carcass cords is larger than Young's modulus of the first carcass cords.

A pneumatic tire 1 comprises a carcass 6 comprising a carcass ply (6A) comprising a main body portion (6a) and turned up portions (6b), and bead apex rubbers 8. Each of the bead apex rubbers 8 comprises a first rubber portion 10 and a second rubber portion 11 provided on an outer side in a tire axial direction of the first rubber portion and having smaller rubber hardness than the first rubber portion. A ratio H1/H2 of a height (H1) of an outer end (10e) in a tire radial direction of the first rubber portion 10 from a bead base line (BL) and a height (H2) of an outer end in the tire radial direction of each of the turned up portions (6b) from the bead base line (BL) is in a range of from 1.4 to 1.7.

A tire having a radial carcass reinforcement, made up of a single layer of reinforcing elements anchored in each of the beads by being turned up around a bead wire, reinforced by a stiffener. In the sidewall of the tire, the profile of the outer surface of the tire is at a constant distance from the carcass reinforcement layer between the points F and A, and meets the outer surface of the bead at the point C, forming two successive circular arcs.

A tire of the “bias belted” type for a motorbike comprises: a tread (2) connected by two sidewalls (3) to two beads (4). A crown reinforcement (5) is radially on the inside of the tread (2) and comprises at least one crown layer (51, 52), such a crown layer (51, 52) comprising mutually parallel reinforcers. A carcass reinforcement (6) is radially on the inside of the crown reinforcement (5) and comprises at least two carcass layers (61, 62, 63), each comprising mutually parallel reinforcers, and crossed from one carcass layer to the next. The reinforcers of each crown layer (51, 52) form, with the circumferential direction (XX′), an angle between 15° and 25° in the equatorial plane (XZ), and the reinforcers of each carcass layer (61, 62, 63) form, with the circumferential direction (XX′), an angle between 40° and 50° in the equatorial plane (XZ).