Patent ID: 7404423

Claim:
A pneumatic tire having a plurality of blocks sectioned by grooves on a tread portion, comprising: a plurality of communication grooves, each communication groove extending linearly from one shoulder to another shoulder; and a plurality of block units, each block unit including a single center block and a pair of side blocks arranged so as to sandwich the center block from both sides thereof and these blocks being arranged along the communication groove, wherein aspect ratios of each center block and each side block in a plan view of the tread portion are approximately equal to each other, each aspect ratio being a ratio of a length of a shorter side to a length of a longer side of a rectangle surrounding each center block or side block, each rectangle being defined by parallel and perpendicular straight sides, the parallel straight sides being parallel to a straight line connecting the gravity centers of the pair of side blocks, the perpendicular straight sides being perpendicular to the straight line, the center block and the side blocks are arranged such that a longitudinal direction of the rectangle surrounding the center block and a longitudinal direction of the rectangle surrounding the side block are approximately orthogonal to each other, and a size ratio of a shorter side of the rectangle surrounding the center block to a longer side of the rectangle surrounding the side block is in a range of 0.9 to 1.10.