Pneumatic tire

A pneumatic tire having a specified rotation direction, comprising:

• a plurality of circumferential main grooves formed on a tread surface and extending in a tire circumferential direction;
• a plurality of lug grooves formed on the tread surface and extending in a tire lateral direction;
• a plurality of blocks wherein both sides of each block are defined in the tire circumferential direction by the lug grooves and at least one end portion of each block being defined in the tire lateral direction by the circumferential main grooves;
• and
• a plurality of block rows formed by aligning a plurality of the blocks in the tire circumferential direction;
• wherein
• given, a region in the tread surface inward from shoulder circumferential main grooves that are the circumferential main grooves positioned outermost in the tire lateral direction among the plurality of circumferential main grooves, as an inner region, and another region in the tread surface outward from the shoulder circumferential main grooves in the tire lateral direction as outer regions,
• the inner region comprises a plurality of the block rows aligned in the tire lateral direction;
• the blocks each comprise at least one narrow groove that opens to at least one of a circumferential main groove or a lug groove, and defines each block into a plurality of small blocks,
• the blocks positioned in the inner region are defined into three or more of the small blocks by the narrow grooves, wherein the at least one narrow groove comprises a single lateral narrow groove extending across each block in the tire lateral direction and defining multiple of the small blocks in the tire circumferential direction, and the at least one narrow groove comprises at least one narrow groove opening to at least one lug groove;
• the blocks positioned in the outer regions are defined into a number of small blocks by the narrow grooves, the number being at least one less than the number of the small blocks defined in the block positioned in the inner region,
• the small block that, among the plurality of small blocks belonging to a block of the blocks, comprises a portion of the block positioned on a frontmost side in a tire rotation direction is a leading-side block,
• the small block that, among the plurality of small blocks belonging to a block of the blocks, comprises a portion of the block positioned on a backmost side in the tire rotation direction is a trailing-side block, and
• the leading-side block has a surface area less than that of the trailing-side block.