Patent ID: 8869852

Claim:
A run flat tire comprising at least 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 so as to envelop bead fillers that are disposed on an outer circumferential side of the bead cores, wherein a plurality of belt layers is disposed on an outer circumferential side of the carcass layer in a tread portion, a belt cover layer is disposed on the outer circumferential side of the belt layers, and a rubber side reinforcing layer having a falcated cross-section is disposed between the carcass layer and an inner liner layer of a side wall portion; wherein when Ga is a rubber thickness measured on a line normal to the 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 measured 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 0.65Gb<Ga<0.85Gb; and when Gc is a rubber thickness measured 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 0.85Ga<Gc<1.00Ga; and a rubber rim cushion is provided on the outer wall surface side of the bead portion and a rubber side filler is embedded in the outer wall surface side of the side wall portion, extending in a tire radial direction, having a maximum thickness at a position where the rubber thickness between the carcass layer and the outer wall surface of the side wall portion is greatest, and gradually thinning vertically in the tire radial direction; a relationship between a 100% modulus Ms of the rubber forming the rubber side filler and a 100% modulus M of the rubber forming the rubber side reinforcing layer is such that 0.7M≦Ms≦1.0M; a relationship between a 100% modulus Mc of the rubber forming the rubber rim cushion and a 100% modulus Ms of the rubber forming the rubber side filler is such that 0.7Ms≦Mc≦1.3Ms; a relationship between a cross-sectional area Df of the bead filler and a cross-sectional area Ds of the rubber side filler is such that Df≦0.4Ds; and a relationship between the cross-sectional area Ds of the rubber side filler and a cross-sectional area D of the rubber side reinforcing layer is such that 0.2D≦Ds≦0.6D.