Patent ID: 6918420

Claim:
A pneumatic tire comprising a tread portion provided with at least one wide circumferential groove, the wide circumferential groove extending continuously in the tire circumferential direction and having a groove width GW of not less than 5% of the ground contacting width TW, the wide circumferential groove provided in the groove bottom with a groove bottom rib, the groove bottom rib extending continuously along the overall length of the wide circumferential groove, the groove bottom rib having a height Hr in a range of from 0.5 to 3.0 mm and a base width Wr in a range of from 10 to 30% of the groove width GW, and the groove bottom rib provided in the top face with a single small groove having a depth Dr of less than the height Hr, wherein the groove bottom of the wide circumferential groove is provided on each side of the groove bottom rib with knurled parts intermittently disposed in the longitudinal direction of the wide circumferential groove, and the knurled parts are each made up of small ribs extending crosswise to the longitudinal direction of the wide circumferential groove, wherein the knurled parts are provided only on said groove bottom.