Pneumatic radial tire for passenger vehicles

A tire-ring assembly formed by assembling a pair of bead portions of a passenger vehicle pneumatic radial tire with a rim, the tire-rim assembly comprising:

• a carcass composed of plies of radially arranged cords toroidally extending between the pair of bead portions;
• and
• a belt,
• wherein a W/L ratio of a section width W to an outer diameter L of the tire is 0.25 or less,
• an air volume of the tire is 15000 cm3 or more, and
• W is equal to or larger than 145 mm,
• wherein the tire-rim assembly is inflated under pressure and filled only with gas,
• wherein the passenger vehicle pneumatic radial tire is a tubeless tire,
• wherein an aspect ratio of the passenger vehicle pneumatic radial tire is greater than or equal to 50 and less than 70,
• wherein W and D satisfy:
• 0.30<W/D<0.52, where D represents a rim diameter of the tire,
• wherein the rim diameter of the tire is greater than or equal to 457.2 mm and less than or equal to 533.4 mm, and
• wherein the outer diameter of the tire is greater than or equal to 642.1 mm and less than or equal to 725.9 mm.