Pneumatic tire

A pneumatic tire, comprising:

• a tread portion extending in a tire circumferential direction and having an annular shape;
• a pair of sidewall portions disposed on opposite sides of the tread portion;
• a pair of bead portions disposed toward the inside of the sidewall portions in a tire radial direction;
• a bead core provided in each of the bead portions;
• a carcass layer mounted between the pair of bead portions;
• and
• a side reinforcing layer provided toward the inside of the carcass layer in the sidewall portion in a tire lateral direction and having a crescent-shape in cross-section;
• wherein
• the bead core comprises at least one bead wire wound in the tire circumferential direction,
• a plurality of circumferential portions of the bead wire form at least one row arranged in the tire lateral direction and a plurality of layers overlapping in the tire radial direction,
• a maximum width W0 of the bead core, a width W1 of one of the layers, which is located at an innermost side in the tire radial direction, and a width W2 of another of the layers, which is located at an outermost side in the tire radial direction, satisfy relationships W1>W2 and W2≤0.5×W0,
• the layer of the plurality of layers, having the maximum width W0, is located toward the inside in the tire radial direction of a center position of the bead core in the tire radial direction,
• when a polygonal shape formed by common tangent lines of the plurality of circumferential portions of the bead wire in a meridian cross-section is defined as an outer shape of the bead wire, internal angles α, β of corner portions located on opposite ends of one side of the outer shape, which is located toward the inside in the tire radial direction, satisfy relationships α>90° and β>90°,
• a peripheral length L0 of the outer shape, a length L1 of the side of the outer shape, which is located toward the inside in the tire radial direction, a length L2 of another side of the outer shape, which is connected to the side located toward the inside in the tire radial direction and which is inclined at a bead toe, and a length L3 of another side of the outer shape, which is connected to the side located toward the inside in the tire radial direction and which is inclined at a bead heel, satisfy relationships 0.25≤(L1+L2)/L0≤0.40 and 1.0≤(L1+L2)/(2×L3)≤2.5,
• the carcass layer comprises a body portion extending from the tread portion through each of the sidewall portions to each of the bead portions, and a folded back portion folded at each of the bead portions and curved along a periphery of the bead core, and extending toward each of the sidewall portions while contacting the body portion from an outer end position of the bead core in the tire radial direction, and
• when an auxiliary line A0 being perpendicular to the carcass layer through an intersection point between an outline of an outer surface of the sidewall portion and a straight line separated from the bead toe by 20 mm toward the outside in the tire radial direction and extending in parallel with the tire radial direction, an auxiliary line A1 separated from the auxiliary line A0 by 5 mm toward the inside in the tire radial direction and being parallel with the auxiliary line A0, and an auxiliary line A2 separated from the auxiliary line A0 by 5 mm toward the outside in the tire radial direction and being parallel with the auxiliary line A0 are drawn in the meridian cross-section, a cross-sectional area SR of a portion of the side reinforcing layer, which is present between the auxiliary line A1 and the auxiliary line A2, and an area SB of a closed region formed by the body portion and the folded back portion of the carcass layer satisfy a relationship 0.4≤SB/SR≤2.5.