A pneumatic tire comprises a carcass which comprises a carcass ply composed of a main portion extending between bead portions and a pair of turned-up portions turned-up around respective bead cores. The bead portion is provided with: a primary bead apex rubber disposed between the carcass-ply main portion and the carcass-ply turned-up portion; an insulation rubber layer extending radially outwardly through between the carcass-ply main portion and the carcass-ply turned-up portion; and a subsidiary bead apex rubber layer disposed on the axially outside of the carcass-ply turned-up portion. The radially outer edge of the insulation rubber layer is located radially outside the radially outer edge of the subsidiary bead apex rubber layer. The complex elastic modulus of the insulation rubber layer is equal to or greater than the complex elastic modulus of the topping rubber of the carcass ply.

Provided is a pneumatic tire. One terminal of a carcass layer extends to a ground contact edge of a tread portion positioned on an opposite side with respect to a tire center line as a reference. The carcass layer has a double layer structure including an inner layer positioned inward in a tire radial direction in a tread region and an outer layer positioned outward in the tire radial direction of the inner layer in the tread region. A cord angle in the carcass layer in a tread central region with respect to a tire circumferential direction is different from a cord angle in at least one of the inner layer and the outer layer of the carcass layer in a side region with respect to the tire circumferential direction.

A tire comprises shoulder blocks and middle blocks having ground contacting surfaces respectively provided with narrow grooves and each including a circumferential groove portion. The tire further comprises bead apex rubbers each extending from respective one of bead cores and each of the bead apex rubbers includes an extended portion extending to a position on an inner side in a tire axial direction of a first reference line passing through the circumferential groove portion of each of the shoulder blocks.

A tire 1 for motorcycles comprises a carcass 6, a belt layer 7, and a tread rubber 2G. The belt layer 7 includes at least one reinforcing cord coated with rubber and spirally wound. In a meridian section passing through a tire rotational axis of the tire 1 in a standard state, a width BW of the belt layer 7 in a tire axial direction is in a range of from 60% to 80% of a tread width TW. The tread rubber 2G has a thickness at a tire equator (C) in a range of from 70% to 90% of thickness at tread edges (2t).

In a tire 2 for a two-wheeled automotive vehicle, a carcass ply 24 is extended on and between one bead 8 and the other bead 8 along inner sides of a tread 4 and sidewalls 6, and includes a main portion 24a and turn-up portions 24b, which are formed by the carcass ply 24 being turned up around the beads 8 from an inner side toward an outer side in an axial direction. An outer end Pp of each turn-up portion 24b is positioned outward of a tread end Pe in a radial direction. A band 14 is positioned between a belt 12 and the tread 4, such that the band 14 covers the belt 12. An outer end P1 of an inner layer 28 layered over a carcass 10 and the outer end Pp of the turn-up portion 24b are positioned facing each other.

A radial tire includes a pair of bead cores, a carcass layer having one or more carcass plies extending from one of the bead cores to another of the bead cores, a tread portion circumferentially encircling the toroidal form of the carcass layer, and a belt structure. The belt structure includes a radially innermost main belt layer, a first, unreinforced cushion layer disposed on a radially outer side of the main belt layer, a second, unreinforced cushion layer disposed on a radially outer side of the first cushion layer, and a protective belt layer disposed between a radially outer side of the second cushion layer and a radially inner side of the tread portion. A radially outermost layer of the main belt layer has reinforcement cords with a specified diameter. The first cushion layer has a radial thickness between 0.5 and 4.0 times the specified diameter.

A pneumatic tire has a rim strip rubber. A radial height of the rim strip rubber on the basis of an outer diameter position of a bead core is equal to or more than 70% of a radial height of a tire outer diameter position. An upper end of a side reinforcing layer is arranged closer to an outer side radially than an upper end of a bead filler. A distance from a tire maximum width position to the upper end of the side reinforcing layer is equal to or less than 5 mm. The maximum thickness Tw of the rim strip rubber between the upper end of the bead filler and the upper end of the side reinforcing layer is greater than the maximum thickness Tm of the rim strip rubber closer to the outer side radially than the upper end of the side reinforcing layer.

In a pneumatic tire 2 according to the present invention, in the vicinity of a bead 10 portion, a main portion 42 of a carcass ply 40 is passed through the vicinity of a neutral surface. A tensile force and a compressive force applied to the main portion 42 are small. In the tire 2, occurrence of pinch cut is suppressed. In addition, this structure alleviates a force applied to the main portion 42 even during run-flat running. In the tire 2, damage is less likely to occur even during run-flat running for a long period of time. The tire 2 has excellent run-flat durability. Furthermore, in the tire 2, an increase in the vertical stiffness constant or weight thereof is suppressed.

In a pneumatic tire, a turned back portion of a carcass layer contacts a body portion of the carcass layer in a cross-sectional view in a tire meridian direction to form a closed region surrounding bead cores. A rubber occupancy ratio in the closed region is in a range of 15% or less. The bead cores have a predetermined wire arrangement structure formed by arranging wire cross sections of bead wires in the cross-sectional view in the tire meridian direction. Additionally, a self-contact height (CH) of the carcass layer and a circumferential length (L) of the wire arrangement have a relationship 1.0CH/L10.0.

In a tire 2, each load support layer 22 extends from a side portion 24 of the tire 2 to a radially inner side of a belt 14 at an inner side of a carcass 12. A ratio (SP/WB) of a width SP from an equator plane to an outer edge 48 of the load support layer 22, relative to a width WB from the equator plane to an edge of the belt 14, in an axial direction is equal to or greater than 0.1 and equal to or less than 0.6.