Abstract: A pneumatic tire having a tread rubber layer disposed radially outside a carcass, a sidewall rubber layer disposed axially outside the carcass in each sidewall portion, the sidewall rubber layer softer than the tread rubber layer, a protective rubber layer disposed on the outer surface of the sidewall rubber layer, the protective rubber layer made of a fiber-reinforced rubber composition contains 10 to 50 parts by weight of short fibrous reinforcements, 20 to 70 parts by weight of carbon black, and 100 parts by weight of rubber base consisting of 20 to 100 parts by weight of natural rubber or isoprene rubber and 80 to 0 parts by weight of butadiene rubber, the short fibrous reinforcements oriented in the tire circumferential direction.

Abstract: A steering stability in a pair of pneumatic radial front and rear tires is considerably improved without sacrificing the tire durability by making a circumferential rigidity of an auxiliary belt in the front tire at a portion corresponding to a central zone of a belt in widthwise direction thereof larger than that of an auxiliary belt in a rear tire at the portion corresponding to the central zone of the belt in widthwise direction thereof.