Patent ID: 7849895

Claim:
A pneumatic tire comprising at least one circumferential wide major groove, a plurality of transverse grooves, and a narrow circumferential minor groove, wherein, the circumferential wide major groove being provided in a center region in a tire width direction of a tread, the circumferential wide major groove being extended in a tire circumferential direction, each of the transverse grooves being extended from a tread end toward the circumferential wide major groove while inclined with respect to the tire circumferential direction, the narrow circumferential minor groove being arranged on an outside of the circumferential wide major groove in a tire axis direction, the narrow circumferential minor groove being extended in the tire circumferential direction, a groove width of the narrow circumferential minor groove is set narrower than that of the circumferential wide major groove, the tread having a plurality of blocks which are zoned by the circumferential wide major groove, at least one of the transverse grooves, and the narrow circumferential minor groove, the tread having a directional tread pattern in which the each transverse groove being sequentially in contact with a road surface from a tire equatorial plane side toward the tread end of the transverse grooves during an on-load rotating operation, a width and a depth of the narrow circumferential minor groove in an area where the narrow circumferential minor groove zones the block are decreased from a kickout side toward a stepping-on side with respect to the block during the on-load rotating operation, the narrow circumferential minor groove includes a first end connected to one of the plurality of transverse grooves and a second end connected to another of the plurality of transverse grooves and two side groove walls that each extend between the ends, the depth of the narrow circumferential minor groove is increased toward the kickout side from a portion of the narrow circumferential minor groove where the side groove walls of the narrow circumferential minor groove are in contact with one another, and the narrow circumferential minor groove includes a flat bottom which is parallel to the tread and is disposed at a portion of the narrow circumferential groove where the side groove walls of the narrow circumferential groove are not in contact with one another.