In a pneumatic tire, a groove depth H1 of each of first and second inclined lug grooves over an entire region from an opening portion to a corresponding one of first or second circumferential main grooves to a terminating end portion within a center land portion has a relationship with a maximum groove depth Hg of the corresponding one of the first or second circumferential main grooves represented by 0.80≤H1/Hg≤1.00. Additionally, a maximum groove depth H2 of each of first and second lateral grooves has a relationship with a groove depth H1e at a terminating end portion of the corresponding one of the first and second inclined lug grooves represented by 0.70≤H2/H1e≤0.90.

A tire for running on rough terrain for which an intended tire rotational direction is specified. The tread portion is provided with blocks raised from a tread base portion. Each block has a first side wall surface comprising a radially outer portion extending substantially straight and radially inwardly, while inclining toward the toe side in the intended tire rotational direction, and a radially inner portion extending from the radially outer portion to the tread base portion while curving in an arc shape. The radially outer portion has a radial length of from 30% to 70% of a radial height of the block.

A tire for running on rough terrain for which an intended tire rotational direction is specified, and which comprises a tread portion provided with crown blocks disposed on the tire equator. Each of the crown blocks comprises a V-shaped crown block main portion which bends convexly toward a circumferential direction opposite to the intended tire rotation direction, and only two crown fin portions projecting from the crown block main portion toward the above-said circumferential direction opposite to the intended tire rotation direction.

A tire comprises a tread portion 2 provided with a first main groove 3 and a second main groove 4 each extending in a zigzag manner and a land region 10 defined between them. The land region 10 is provided with a longitudinal sipe 15 extending in a zigzag manner in the tire circumferential direction, first lug grooves 16, and second lug grooves 17. The land region 10 comprises first blocks 21 divided by the longitudinal sipe 15 and the first lug grooves 16, and second blocks 22 divided by the longitudinal sipe 15 and the second lug grooves 17. Each of the first blocks 21 and the second blocks 22 is provided with not less than three transverse sipes 25 extending across the entire width of the each of the first blocks 21 and the second blocks 22.

A pneumatic tire comprises in a tread surface thereof a land portion that comprises a plurality of blocks. Each of the blocks comprises in a contact patch thereof a plurality of narrow shallow grooves and a plurality of recessed portions disposed separated from the narrow shallow grooves. The narrow shallow grooves have a groove width of from 0.2 mm to 0.7 mm and a groove depth of from 0.2 mm to 0.7 mm. The recessed portions have the same depth as the narrow shallow grooves.

A heavy-duty tire includes a tread part formed such that the tread part includes a crown profile including tire equator, and a pair of shoulder profiles extending from outer sides of the crown profile to tread edges. In a tire cross section including tire rotation axis in 5% internal pressure state in which the tire is mounted to a normal rim, filled with air at internal pressure of 5% of normal internal pressure and loaded with no load, each of the crown and shoulder profiles has an arc shape convex toward tire radial direction outer side such that ratio Rc/Rs of curvature radius Re of the crown profile to curvature radius Rs of each shoulder profile is 7.0 or more, and a tire axial direction distance from the equator to a connecting point between the crown profile and each shoulder profile is 0.70 or more times a tread half width.

A pneumatic tire, includes: an annular-shape tread portion; a sidewall portions; and bead portions. JIS hardness of tread rubber is within a range of 40 to 60 and snow traction index is 180 or higher. A rib positioned between circumferential grooves is demarcated in a center region of the tread portion. Closed grooves are formed in the rib. The closed grooves are inclined with regard to a tire axial direction such that a closed end faces a leading side. A groove wall of the closed groove on the leading side protrudes more outward in the tire axial direction than a groove wall on a trailing side. A difference between angles θ1 and θ2 of the groove walls on the leading and trailing sides of the closed grooves, respectively, with regard to the tire axial direction is within a range of 0°≤θ1-θ2≤5°.

A tire tread having features that improve thermal wear performance is provided. A tread block is provided with an aperture. The aperture is positioned and sized in a manner that reduces stresses and/or strains in the tread block so as to reduce thermal wear. Certain variations in the depth and shape of the aperture are provided. Such tread feature can provide for a tire capable of operating at higher speeds for a given load.

A pneumatic tire includes a tread portion provided with a circumferentially extending zigzag shoulder main groove arranged proximate to a tread edge, and a plurality of shoulder lateral grooves each extending axially outwardly from the shoulder main groove. Each of the shoulder lateral grooves includes a first portion and second portion. The first portion includes a first groove wall and an axially inner end connected to the shoulder main groove. The second portion is arranged axially outward of the first portion and includes a second groove wall. The second portion has a groove width and a groove depth greater than those of the first portion. The first groove wall of the first portion and the second groove wall of the second portion are smoothly continued.

The present technology provides a heavy duty pneumatic tire with a tread portion having a tread pattern including: a pair of circumferential primary grooves defined in a wave-like shape and extending in the tire circumferential direction; center lug grooves; center blocks; and circumferential secondary grooves extending in regions of the center blocks and open to the center lug grooves. The center lug grooves have two groove turning portions turned in a bend shape or a curved shape. The circumferential secondary grooves extend in an inclined manner relative to the tire circumferential direction. An inclination angle (θ.sub.4) of the circumferential secondary grooves relative to the tire circumferential direction is different from an inclination angle (θ.sub.1) of portions of the circumferential primary grooves relative to the tire circumferential direction, the portions extending toward the same side as a side in the tire width direction, toward which the circumferential secondary grooves are inclined.