RUN-FLAT TIRE

The run flat tire according to this disclosure comprises a tread portion, sidewall portions, bead portions, a side-reinforcing rubber having a crescent-shaped cross section, and a carcass. A part of the side-reinforcing rubber is a low elastic portion with a lower elastic modulus than other portion, and the low elastic portion is located in an area, in the tire radial direction, of 50% or more and 80% or less of the tire cross-sectional height from the bead baseline. In a reference condition, an elastic modulus of the low elastic portion is 80% or less of an elastic modulus of the other portion. When the maximum thickness of the low elastic portion, measured in the direction of a perpendicular line from the carcass down to the tire inner surface, is t1 and the thickness of the other portion, measured in the direction of the perpendicular line, is t2, the ratio t1/t2 is 0.2 or more and 3 or less. The tire maximum width in the reference condition is the center value or more and the upper limit or less of the tire maximum width specified in the standard, and the tire maximum width position in the reference condition is located at the position, with a distance of more than 50% of the tire cross-sectional height, outward in the tire radial direction from the bead baseline.