Patent ID: 8905101

Claim:
A run flat tire comprising one layer of a carcass layer provided around bead cores embedded in a left-right pair of bead portions and folded over from a tire inner side toward a tire outer side, wherein a plurality of belt layers is disposed in an outer circumferential side in a tread portion, a belt cover layer formed from organic fiber cords is disposed on the outer circumferential side of the belt layers, and a side reinforcing layer having a falcated cross-section is disposed between the carcass layer and an inner liner layer in a side wall portion; wherein a relationship between a tire cross-sectional height SHi on an inner side in a tire radial direction and a tire cross-sectional height SHo on an outer side in the tire radial direction, demarcated by a maximum tire width position when the run flat tire is assembled on a JATMA regulation standard rim and inflated to an air pressure of 180 kPa, is 0.7<SHi/SHo<0.9; an intersection P of a line tangent to an intersection S of a straight line Q in a tire axial direction passing through a midpoint of the tire cross-sectional height SHo and a tire outer wall and an tire external diameter line Z is positioned more to a tire equatorial plane side than an endpoint of a region R that corresponds to 90% of a rim width HRW of the standard rim having the tire equatorial plane as a center; an angle α of a straight line connecting, in the tread surface, a point O on the tire equatorial plane and a point R′ on a shoulder side corresponding to 110% of a tire ground contact width TW having the tire equatorial plane as a center, with respect to the tire axial direction, is from 7.5° to 10°; a folded up end of the carcass layer is positioned in a region within 15 mm from an outer peripheral surface of the bead core toward the outer side in the tire radial direction and a height Hf of an outer peripheral edge of the bead filler is from 40% to 70% of a tire cross-section height SH; when Ga is a rubber thickness, taken on a line normal to a rim line at an outer wall surface of the bead portion, between the carcass layer and an outer wall surface of the side wall portion; and Gb is a maximum rubber thickness taken on a line normal to the carcass layer between the carcass layer and the outer wall surface of the side wall portion, a relationship between Ga and Gb is 0.60Gb<Ga<0.85Gb; and when Gc is a rubber thickness taken on a line normal to the rim line between the carcass layer and a tire inner wall surface, a relationship between Gc and Ga is 0.75Ga<Gc<1.00Ga.