Patent ID: 8881782

Claim:
A pneumatic tire comprising: at least four circumferential main grooves extending in a tire circumferential direction, and a plurality of rib-like land portions that are partitioned and formed by the circumferential main grooves in a tread portion, wherein a pair of the circumferential main grooves on an outermost side in a tire width direction are “shoulder main grooves”; left and right land portions of the land portions partitioned by the shoulder main grooves on an inner side in the tire width direction are “second land portions”; a first of the second land portions is an “outer side second land portion”, and a second of the second land portions is an “inner side second land portion”, the outer side second land portion comprises: an L-shaped narrow groove formed by connecting a width direction groove portion extending from an edge portion on an outer side in the tire width direction of the outer side second land portion toward the inner side in the tire width direction, and a circumferential direction groove portion extending substantially parallel to the tire circumferential direction and terminating in an interior portion of the outer side second land portion; and a penetrating sipe extending from a first of the circumferential main grooves to a second of the circumferential main grooves, penetrating the outer side second land portion in the tire width direction and intersecting the circumferential direction groove portion; a portion of the outer side second land portion surrounded by the circumferential main groove, the L-shaped narrow groove, and the penetrating sipes is referred to as a “short portion”, a length D 2 in the tire circumferential direction of the edge portion of the short portion on the outer side in the tire width direction and a length D 3 in the tire circumferential direction of an edge portion of the short portion partitioned by the circumferential direction groove portion are such that 0.7≦D 3 /D 2 ≦1.3; and a plurality of the L-shaped narrow grooves and a plurality of the penetrating sipes are disposed at a predetermined pitch in the tire circumferential direction, and adjacent L-shaped narrow grooves are disposed so as to be mutually isolated.