Patent ID: 7647958

Claim:
A pneumatic tire comprising a tread surface having a specified tire rotation direction, a main groove extending in a circumferential direction of the tire being provided on an equatorial plane of the tire in the tread surface, right and left first inclination grooves being disposed at prescribed intervals in the circumferential direction of the tire, the right and left first inclination grooves extending from the main groove toward opposite sides of the tire in a widthwise direction of the tire beyond ground contact ends of the tire in an inclined manner toward a reverse rotation direction of the tire, right and left second inclination grooves being provided on opposite sides of the main groove at prescribed intervals in the circumferential direction of the tire, the right and left second inclination grooves extending across the right and left first inclination grooves in such an inclined manner with respect to the circumferential direction of the tire that tire reverse rotation direction sides of the second inclination grooves are more away from the main groove than tire rotation direction sides of the second inclination grooves, blocks being defined on the opposite sides of the main groove by the main groove, right and left first inclination grooves and right and left second inclination grooves, wherein: the right and left second inclination grooves are disposed at symmetrical positions with respect to the equatorial plane of the tire; the blocks comprise right and left first blocks defined by tire rotation direction side portions of the right and left second inclination grooves, main groove and right and left first inclination grooves, and right and left second blocks defined by tire reverse rotation direction side portions of the right and left second inclination grooves, main groove and right and left first inclination grooves, the first blocks each having a circumferential length LA, the second blocks each having a circumferential length LB, the circumferential length LB being greater than the circumferential length LA; and the main groove has first main groove portions between the right and left first blocks and second main groove portions between the right and left second blocks, widths of the first main groove portions between a first corner of a right first block and a first corner of a left first block being less than widths of the second main groove portions between a second corner of a right second block and a second corner of a left second block, wherein the first corners of the first blocks are located at the tire reverse rotation direction side of the first blocks and the second corners of the second blocks are located at the tire reverse rotation direction side of the second blocks.