Tire including: a tread; a pair of sidewalls extending substantially inward radially from ends of the tread; a pair of beads positioned substantially radially inwardly of the sidewalls; and a clinch portion extending from the sidewalls to the beads. A concave curved surface extends on an outer surface of the clinch portion in a circumferential direction. A convex curved surface formed on a radially outer side end of a rim flange is engageable with the concave curved surface. A ratio R1/R of curvature radius R1 of the concave curved surface to a curvature radius R of the convex curved surface of the rim flange satisfies 1.7R1/R2.5. The curvature radii R1 and R of the concave and convex curved surfaces, respectively, are each a radius of curvature of an arc on a cross-section taken along a plane including a tire center axis.

A tire manufacturing method includes making a master batch, using the master batch to make a rubber composition, and making a green tire. The master batch is made wherein a carbon-black-containing pre-coagulation rubber latex is coagulated to obtain a coagulum; a compound according to Formula (I) is added to the water-containing coagulum;

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wherein R.sup.1 and R.sup.2 each indicates a hydrogen atom, an alkyl group having 1 to 20 carbons, an alkenyl group having 1 to 20 carbons, or an alkynyl group having 1 to 20 carbons, R.sup.1 and R.sup.2 may be the same or different, and M.sup.+ indicates sodium ion, potassium ion, or lithium ion; and the compound according to Formula (I) is dispersed within the coagulum. The green tire is provided with unvulcanized rubber sheeting made up of the rubber composition, chafer(s), carcass ply or plies, and bead filler(s).

A pneumatic tire according to the invention includes: a pair of left and right beads 3 each including a bead cores 3a and bead fillers 3b; a carcass ply 5 extended around the bead cores 3a; and an inner liner 4 arranged on an inner peripheral side of the carcass ply 5, and is characterized in that the carcass ply 5 is wound up around the bead cores 3a from the outside in the direction of width of tire to the inside in the direction of width of tire, and a distortion restraining layer 7 configured to restrain distortion of the winding ends 5a of the carcass ply 5 is provided between the bead fillers 3b and the carcass ply 5 so as to overlap with a wind-up ends 5a of the carcass ply 5.

A tyre (1), comprising: two toroidal bead portions (12), each housing an annular bead bundle (121); a toroidal body ply (10), folded, at each of its transversal ending portions (101), about a respective bead bundle (121) forming a respective turn-up (14); two bead fillers (20), one for each bead portion, each in contact with a respective bead bundle (121) and at least partly enclosed by a respective turn-up (14),

which tyre (1) further comprises two elastomeric crack control members (21), one for each bead portion (12), wherein each crack control member (21) extends at a body ply ending (101), externally to the respective turn-up (14), and each crack control member (21) is made by a couple of strips having a differentiated stiffness along their transversal section, with a lower stiffness at a first strip (201, 211) adjacent to the body ply ending (101) and a higher stiffness at a second strip (202, 212) in contact with the respective bundle (121),

so that the first lower stiffness strip defines a preferential propagation path for any tyre crack originating at the body ply folded ending (FIG. 2).

Edge separation in a turned-up end portion (5E) of a carcass ply (5) is suppressed. In a pneumatic tire comprising a bead core (4) embedded in a bead portion (3) and a carcass ply (5) turned up and locked around the bead core (4), a rubber sheet (10) is prepared using a wet masterbatch containing natural rubber and/or polyisoprene rubber and carbon black, and the rubber sheet (10) is arranged on at least one of front and back sides of the turned-up end portion (5E) of the carcass ply (5).

Provided is a pneumatic tire in which fiber reinforced layers on an outer side of a steel reinforced layer in a width direction each include fiber cords arranged in one direction, the fiber cords being oriented to cross each other between layers, a radially outer end of one of the fiber reinforced layers being radially outward of a turned-up end portion of a carcass layer, a radially outer end portion of another one of the fiber reinforced layers being radially inward of the turned-up end portion and radially outward of a line segment (K). Radially inner end portions of the fiber reinforced layers are inward in the width direction of a line segment (J), and cord angles A and B of the fiber reinforced layers satisfy 20|A|45 or 70|A|90, and 20|B|45 or 70|B|90.

In a pneumatic tire, a bead filler is on an outer circumference of a bead core, a carcass turned up end is inward of an outer diameter side end of the bead filler, the carcass end is spaced from a carcass body, a steel reinforcement is in each bead, a sidewall rubber extends from the sidewall to the bead, and a support layer is between the bead filler and the sidewall rubber to cover the carcass end and an end of the steel reinforcement, the support layer extending toward an outer diameter side and contacting the carcass body on an outer diameter side of the bead filler outer diameter side end, and a 100% modulus of the support layer is at least 1.5 times that of the bead filler, and the sidewall rubber, the bead filler and the sidewall rubber being adjacent to the support layer.

Provided is a pneumatic tire in which fiber reinforced layers on an outer side of a steel reinforced layer in a width direction each include fiber cords arranged in one direction, the fiber cords being oriented to cross each other between layers, a radially outer end of one of the fiber reinforced layers being radially outward of a turned-up end portion of a carcass layer, a radially outer end portion of another one of the fiber reinforced layers being radially inward of the turned-up end portion and radially outward of a line segment (K). Radially inner end portions of the fiber reinforced layers are inward in the width direction of a line segment (J), and cord angles A and B of the fiber reinforced layers satisfy 20|A|45 or 70|A|90, and 20|B|45 or 70|B|90.