Patent ID: 7490645

Claim:
A pneumatic tire comprising a tread portion, and a plurality of fib-like land portions divided by circumferential main grooves extending in a circumferential direction of the tire, in which at least one rib-like land portion is divided into a plurality of blocks arranged in the circumferential direction by lateral grooves which cut across the rib-like land portion, wherein the lateral grooves provided with tie bars which extend from a bottom surface of the lateral groove and which connects circumferentially adjacent blocks to each other, the tie bar is formed with a sipeing which opens at an outer surface of the tie bar and which comprises a zigzag portion extending in a direction of a groove centerline of the lateral groove in a zigzag manner, said zigzag portion of the sipeing provides an identical shape in any cross section parallel to the outer surface of the tie bar, and the zigzag portion is displaced by a displacement amount (La) toward one side and the other side in a direction of the zigzag centerline as the cross section moves from an upper end to a bottom of the sipeing so as to form zigzag displacement portions, a displacement amount (La 2 ) of the zigzag displacement portion disposed lowermost side is smaller than a displacement amount (La 1 ) of the zigzag displacement portion disposed uppermost side, depths (h) of the zigzag displacement portions are equal to each other, and ratio (La/h) of the displacement amount (La) to the depth (h) of the zigzag displacement portion disposed lowermost side is smaller than the ratio (La/h) of the displacement amount (La) to the depth (h) of the zigzag displacement portion disposed uppermost side.