This invention discloses a tire tread comprising: (a) a first tread cap layer comprising a first rubber composition; and (b) a second tread cap layer arranged radially inside of the first tread cap layer comprising a second rubber composition; wherein at 0° C. the rebound resilience of the first rubber composition is within a range of 10% to 25%, the rebound resilience of the second rubber composition is within a range of 15% to 35% and is at least 5% lower than that of the second rubber composition; and wherein at 100° C. the rebound resilience of the first rubber composition is within a range of 45% to 65%, the rebound resilience of the second rubber composition is within a range of 60% to 75% and is at least 3% higher than that of the first rubber composition.

A tire, the speed rating of which is at least V, comprises a tread, having a volumetric void ratio at least equal to 2% and at most equal to 20%, having a central part Pc comprising at least one groove, and two lateral parts PI each having a volumetric void ratio at most equal to 2%. The central part Pc of the tread has an axial width at most equal to one third of the axial width LBDR of the tread, and any portion of the central part Pc of the tread that is circumferentially delimited by two meridian planes separated by a circumferential distance dc equal to one tenth of the outer perimeter P of the tire comprises at least one and at most three grooves that open onto the meridian planes delimiting the portion in question.

A run-flat tire includes a belt reinforcing layer outward of a belt layer in a tire radial direction and reinforcing rubber in sidewall portions. Where a center region is a region of a tread portion in which a center land portion corresponding to a land portion included in land portions in a tread portion and located closest to a tire equatorial plane is positioned, the belt reinforcing layer includes a center reinforcing portion in which more pieces of the belt reinforcing layer are layered at a position of the center region than at positions other than the position of the center region, and in the belt reinforcing layer, a width Wc of the center reinforcing portion in a tire lateral direction with respect to a thickness Gr of the side reinforcing rubber at a tire maximum width position is within a range of 0.5 Gr≤Wc≤2.0 Gr.

A tire includes a tread portion including a ground contact surface, a first rubber layer made of a first cap rubber forming part of the ground contact surface, a second rubber layer made of a second cap rubber disposed radially inwardly of the first rubber layer, and at least one groove portion opening to the ground contact surface. The first cap rubber has a loss tangent tan δ1, and the second cap rubber has a loss tangent tan δ2 greater than the loss tangent tan δ1. The groove portion includes a first indicator in which a bottom of the groove portion locally raises, the first indicator having an outer surface in a tire radial direction. The radially outer surface of the first indicator substantially coincides with a first wear line that is parallel to the ground contact surface and passes through a radially outer surface of the second rubber layer.

A run-flat tire includes: sipes formed in blocks; a belt reinforcing layer on an outer side in a radial direction of a belt layer; and a side reinforcing rubber in sidewall portions, wherein a density of the sipes in a center block is from 0.10 cords/mm or greater to 0.30 cords/mm or smaller, the belt reinforcing layer includes a center reinforcing portion in which more center reinforcing portions are stacked at a center region than at positions other than the center region, a width Wc of the center reinforcing portion is within 0.5 Gr≤Wc≤2.5 Gr with respect to a thickness Gr of the side reinforcing rubber at the tire maximum width position, and an average width of the width Wc of the center reinforcing portion is from 50% or greater to 90% or smaller of a width of the center block.

In a pneumatic tire are defined: a first imaginary line VL1 passing through a ground contact surface in a meridian cross section of a tread, a second imaginary line VL2 passing through a bottom of a shoulder groove and parallel to VL1, an intersection point P between VL2 and a surface of a shoulder land outward of a ground contact edge T in a lateral direction, and an equatorial plane CL. Given A as a distance in the lateral direction between P and CL, B as a groove depth of the shoulder groove, and C as a distance in the lateral direction between T and CL, 0.80≤(B+C)/A≤1.15 is satisfied. Given Q as a distance in the lateral direction between CL and an end of a belt ply that has a shorter dimension in the lateral direction, 0.75≤Q/C≤0.95 is satisfied.

An outer diameter of the pneumatic tire is 350 mm or more and 600 mm or less, and as RW is defined by a rim width of a rim wheel assembled to the pneumatic tire and SW is defined by a tire width of the pneumatic tire, the relation of 0.78≤RW/SW≤0.99 is satisfied, and at least two circumferential main grooves extending to the tire circumferential direction are formed in the tread. The circumferential main groove is formed closer to a tire equatorial line than an outer end in the tire width direction of the belt layer.

The pneumatic tire includes a carcass layer, a belt layer disposed on an outer side of the carcass layer in a radial direction, and a tread rubber disposed on an outer side of the belt layer in the radial direction. Additionally, the carcass layer has a cord angle of 80° or more and 100° or less. Additionally, the belt layer is formed by layering a first reinforcing belt, a second reinforcing belt that is narrower than the first reinforcing belt, and an auxiliary belt that is spaced apart from a tire equatorial plane and disposed between the carcass layer and the first reinforcing belt. Additionally, the first reinforcing belt has a cord angle of 11° or more and 30° or less, the second reinforcing belt has a cord angle of 1° or more and 11° or less, and the auxiliary belt has a cord angle of 55° or more and 70° or less.

The belt layer (50) of the pneumatic tire (10) includes one inclined belt (50 A) having an inclined cord inclined with respect to the tire width direction, and a circumferential belt (50 B) disposed outside the tire radial direction of the inclined belt (50 A) and having a circumferential cord (52) wound along the tire circumferential direction. The inclined cord and the circumferential cord are formed of a predetermined organic fiber. The tread thickness (T1) of the rubber forming the tread portion (20) along the tire radial direction at a tire equatorial line (CL) is 5 mm or less.

Provided is a heavy duty tire having excellent chipping resistance during high-speed running. Included is a heavy duty tire including a tread portion, the tread portion including a shoulder region located axially outward from an axially outermost main longitudinal groove extending in a circumferential direction, the tread portion being provided with a tread rubber consisting of a multilayer structure including a cap rubber layer forming a tread outer surface and a radially innermost base rubber layer, the cap rubber layer in the shoulder region containing at least one rubber component including a polybutadiene rubber and a carbon black, the heavy duty tire satisfying the following relationships (1) to (3): (1) Tb/Tc ≤ 0.50; (2) Eb′/Ec′ ≤ 0.60; and (3) Bca/(Tb/Tc) ≥ 40 wherein Tc, Ec′, Tb, Eb′ and Bca are defined herein.