PNEUMATIC RADIAL TIRE FOR A PASSENGER VEHICLE AND METHOD OF USING THE SAME

A pneumatic radial tire for a passenger vehicle including a carcass (2), which is composed of a ply of carcass cords radially arranged and toroidally provided between a pair of bead portions, and a pair of sidewall portions (5) connected to the bead portions, wherein when the tire is mounted on a rim and applied with internal pressure of at least 250 kPa, a tire cross-sectional width SW and a tire outer diameter OD satisfy a relational expression: OD>-0.0187xSW 2+9.15xSW-380, and a ratio Ts/Tc is 5 to 10, the Ts representing a gauge of the sidewall portion in a tire maximum width portion and Tc representing a diameter of the carcass cords.