Run-flat tire

A run-flat tire comprising:

• a tread portion;
• sidewall portions disposed on opposite sides of the tread portion in a tire lateral direction;
• a belt layer disposed in the tread portion;
• a belt reinforcing layer disposed outward of the belt layer in a tire radial direction;
• a tread rubber layer disposed outward, in the tire radial direction, of the belt reinforcing layer in the tread portion;
• and
• side reinforcing rubber disposed in each of the sidewall portions and including tire radial direction outer end portions located inward of the belt layer in the tire radial direction,
• the tread portion being provided with a main groove extending in a tire circumferential direction and defining a plurality of land portions, and
• assuming that a center region is a region where a center land portion corresponding to the land portion included in the land portions in the tread portion and located closest to a tire equatorial plane is positioned and that shoulder regions are each a region between the corresponding tire radial direction outer end portion of the side reinforcing rubber and a corresponding end portion of the belt layer in the tire lateral direction and that
• an intermediate regions are each a region between the center region and the shoulder region,
• the belt reinforcing layer including a center reinforcing portion located at a position of the center region and in which more pieces of the belt reinforcing layer are layered than at positions other than the position of the center region, and
• in the belt reinforcing layer, a width We of the center reinforcing portion in the tire lateral direction with respect to a thickness Gr of the side reinforcing rubber at a tire maximum width position being within a range of 0.5 Gr≤Wc≤2.0 Gr, the width Wc being varied in the tire circumferential direction.