Patent ID: 7893147

Claim:
A radial tire having a breaker cushion or a side wall packing which is a layer provided on the upper portion of a bead apex comprising a rubber composition containing 20 to 40 parts by weight of carbon black having an iodine adsorption amount of 39 to 75 mg/g and a dibutyl phthalate oil absorption amount of 110 to 121 ml/100 g; and 5 to 25 parts by weight of silica having a BET specific surface area of 119 to 175 m 2 /g based on 100 parts by weight of a rubber component, wherein the rubber component consists only of a natural rubber and wherein the rubber composition has a complex elastic modulus E* which is measured at a measurement temperature of 70° C., an initial strain of 10%, a dynamic strain of ±2% and a frequency of 10 Hz is at least 4 MPa, and a loss tangent tan δ is less than 0.05 in the fore-mentioned rubber composition.