A pneumatic tire mountable on a 15° tapered specified rim includes a bead core, a carcass, a steel cord reinforcing layer, a bead rubber layer, an organic fiber reinforced layer, and a first reinforcing rubber layer. A distance from a second line segment to a third line segment is from 4 mm to 12 mm, a complex modulus of the first reinforcing rubber layer is from 6 MPa to 10 MPa, an elongation at break of the first reinforcing rubber layer is from 300% to 450%, and a difference between a first height and a second height is from 3 mm to 15 mm.

A heavy-duty tire includes a tread part formed such that the tread part includes a crown profile including tire equator, and a pair of shoulder profiles extending from outer sides of the crown profile to tread edges. In a tire cross section including tire rotation axis in 5% internal pressure state in which the tire is mounted to a normal rim, filled with air at internal pressure of 5% of normal internal pressure and loaded with no load, each of the crown and shoulder profiles has an arc shape convex toward tire radial direction outer side such that ratio Rc/Rs of curvature radius Re of the crown profile to curvature radius Rs of each shoulder profile is 7.0 or more, and a tire axial direction distance from the equator to a connecting point between the crown profile and each shoulder profile is 0.70 or more times a tread half width.

The invention is a tyre comprising, in the central part of its crown, at least one undulation (51) of the radially outermost crown layer, having a radial amplitude A at least equal to 1 mm. At least one bead comprises, aside from the radial carcass layer and the bead wire, a radial reinforcing element that is such that the axial distance between the radial reinforcing element and the axially innermost carcass layer is at least equal to 1 mm and at most equal to 12 mm at the point of the radial reinforcing element that is situated 30 mm from the radially innermost point of the bead wire, for a better trade-off between the stiffness of the undulating crown and of the bead.

The pneumatic tire comprises a pair of bead cores, a pair of bead fillers disposed outward of the pair of bead cores in a tire radial direction, a carcass layer disposed folded around the bead cores and the bead fillers, and a steel chafer including an arranged plurality of steel cords, the steel chafer being disposed between the carcass layer and a rim engaging surface. A height Hs of an outer end portion of the steel chafer located outward of the bead fillers in a tire width direction and a rim flange height Hf have the relationship: 0.5Hs/Hf1.0, where the height is measured from a measuring position of a rim diameter.

A heavy-duty tire includes a tread part formed such that the tread part includes a crown profile including tire equator, and a pair of shoulder profiles extending from outer sides of the crown profile to tread edges. In a tire cross section including tire rotation axis in 5% internal pressure state in which the tire is mounted to a normal rim, filled with air at internal pressure of 5% of normal internal pressure and loaded with no load, each of the crown and shoulder profiles has an arc shape convex toward tire radial direction outer side such that ratio Rc/Rs of curvature radius Re of the crown profile to curvature radius Rs of each shoulder profile is 7.0 or more, and a tire axial direction distance from the equator to a connecting point between the crown profile and each shoulder profile is 0.70 or more times a tread half width.

A heavy-duty pneumatic tire includes a carcass ply including a main portion extending between bead cores and a pair of turn-up portions, a first reinforcing layer of a steel cord disposed in each bead portion in a U-shaped manner, and a second reinforcing layer of an organic fiber cord disposed in each bead portion and at least a part of the second reinforcing layer extending in a radial direction of the tire at an axially outward location of the first reinforcing layer. The second reinforcing layer includes an axially inner second ply and an outer second ply. The outer second ply has an inner end positioned below the bead core. The inner second ply has an inner end located axially inward of the inner end of the outer second ply, and has a substantially same length as the outer second ply in a tire cross-section.

A pneumatic tire mountable on a 15 tapered specified rim includes a bead core, a carcass, a steel cord reinforcing layer, a bead rubber layer, an organic fiber reinforced layer, and a first reinforcing rubber layer. A distance from a second line segment to a third line segment is from 4 mm to 12 mm, a complex modulus of the first reinforcing rubber layer is from 6 MPa to 10 MPa, an elongation at break of the first reinforcing rubber layer is from 300% to 450%, and a difference between a first height and a second height is from 3 mm to 15 mm.

A tire 2 includes a tie gum 24 between a carcass 12 and each chafer 22. In the tire 2, an inner liner 20 is formed from a thermoplastic elastomer composition including a styrene-isobutylene-styrene block copolymer. The inner liner 20 has a thickness of not greater than 1.5 mm. The tie gum 24 joins the inner liner 20 and the chafer 22 and has a volume resistivity of not greater than 10.sup.8 .Math.cm.

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.

The pneumatic tire comprises a pair of bead cores, a pair of bead fillers disposed outward of the pair of bead cores in a tire radial direction, a carcass layer disposed folded around the bead cores and the bead fillers, and a steel chafer including an arranged plurality of steel cords, the steel chafer being disposed between the carcass layer and a rim engaging surface. A height Hs of an outer end portion of the steel chafer located outward of the bead fillers in a tire width direction and a rim flange height Hf have the relationship: 0.5Hs/Hf1.0, where the height is measured from a measuring position of a rim diameter.