A circumferential narrow main groove extending in a circumferential direction in a tread of a pneumatic tire. The circumferential narrow main groove includes a narrow portion opening to a road contact surface of the tread and a widened portion having a wider groove width than the narrow portion. The widened portion is at a groove bottom. A groove width ratio (W2/W1) of a maximum groove width W2 of the widened portion to a groove width W1 of the narrow groove portion is in a range 1.5≤(W2/W1)≤4.0, and a cross-sectional area ratio (A2/A1) of a groove bottom-side cross-sectional area A2 to a groove opening-side cross-sectional area A1 in a meridian cross-section is within a range 1.2<(A2/A1)<4.0 when the circumferential narrow main groove is divided into two parts at 50% of a maximum groove depth of the circumferential narrow main groove. The cross-sectional area ratio changes along the circumferential direction.

In a pneumatic tire, a block includes recess/protrusions on a road contact surface. Additionally, a recess/protrusion content of the recess/protrusions is from 0.1 mm to 1.0 mm. A width of the recess/protrusions is from 0.1 mm to 0.8 mm. A recess/protrusion region is where an arrangement interval between adjacent recess/protrusions is not greater than 1.2 mm. A smooth region other than the recess/protrusion region has an arithmetic mean roughness of the road contact surface of the block not greater than 50 μm. A lateral length of the road contact surface of the block in a tire lateral direction is defined. In this case, the block includes the recess/protrusion region and the smooth region in an optional cross-section in a lateral range of not less than 40% of a lateral length of the road contact surface of the block.

A pair of main grooves disposed on both sides of a tire equator of a pneumatic tire and extending along a tire circumferential direction is configured so that a series of bent elements formed by connecting at least five linear groove portions via bend points are continuously and repeatedly arranged in the tire circumferential direction, and the at least five linear groove portions included in each of the bent elements have three or more types of inclination angles with respect to the tire circumferential direction and have five or more types of lengths.

A tire includes a plurality of main lug grooves and a plurality of sub lug grooves that extend in a tire width direction and penetrate a tread surface, and that are arranged at predetermined intervals in a tire circumferential direction. Additionally, the main lug grooves have a maximum groove width Wg1 of 15.0 mm or more and a maximum groove depth of 23.5 mm or more. In addition, the sub lug grooves have a maximum groove width Wg2 that satisfies 0.10≤Wg2/Wg1≤0.35 with respect to the maximum groove width Wg1 of the main lug grooves. Additionally, at least one of the sub lug grooves is disposed between adjacent ones of the main lug grooves.

A heavy truck tire tread with a rib (18) located between first (14) and second (16) tread grooves. A shoulder block (30) is adjacent the rib and at a shoulder edge of the tread, and a decouple groove (32) is present that decouples the shoulder block from the rib. The decouple groove is spaced from and free from engagement with the shoulder edge, and extends at least twice as long in the longitudinal direction than in the lateral direction. The width of the decouple groove is less than widths of the first and second tread grooves. The tread has an average void depth that does not go past a twenty percent line, where the twenty percent line is twenty percent of a full void depth located from an outer surface of the tread, and where the average void depth does not include decouple grooves and tread outboard from the decouple grooves.

A pneumatic tire includes a tread portion molded by sectors divided in a tire circumferential direction. The pneumatic tire includes circumferential grooves, rows of land portions, and sipes. The circumferential grooves extend in the tire circumferential direction in the tread portion. The rows of land portions are defined by the circumferential grooves. The sipes extend in a tire width direction in at least one row of the rows of land portions. The sipes include at least one shallow bottom sipe and regular sipes. The at least one shallow bottom sipe is disposed in a boundary region including a dividing position of each of the sectors. The regular sipes are disposed at positions more separated from the dividing position of each of the sectors than the at least one shallow bottom sipe. The at least one shallow bottom sipe is shallower than the regular sipes.

A pneumatic tire comprises circumferential main grooves extending in the tire circumferential direction and land portions defined by the circumferential main grooves. The land portions are each provided with a plurality of groove units which are sets including a first groove, a second groove, and a third groove. The first groove, the second groove, the third groove are disposed without meeting one another, and radially extend at intervals from each other ranging from 90 degrees to 150 degrees. Additionally, the first groove is a lug groove with the groove width ranging from 1.5 mm to 4.0 mm and has a semi-closed structure, opening to the circumferential main groove or the tire ground contact edge at a first end portion and terminating within the land portion at a second end portion.

A tire includes an outboard tread edge and an inboard tread edge to be located on an outboard side and an inboard side of a vehicle, respectively, circumferentially and continuously extending main grooves, and land portions divided by the main grooves. The land portions include an outboard shoulder land portion, an outboard middle land portion, an inboard shoulder land portion, and an inboard middle land portion. Each of the outboard shoulder land portion, the inboard shoulder land portion, and the inboard middle land portion is provided with axially extending lateral grooves. The outboard middle land portion is provided with outboard middle lateral grooves extending from an edge of the outboard middle land portion on the outboard tread edge side toward the inboard tread edge. The outboard middle lateral grooves are inclined with respect to a tire circumferential direction at angles smaller than those of the lateral grooves.

Tread (1) of a tire for an off-road vehicle, with total width (W) and total thickness of wearable material at least equal to 60 mm. The tread is delimited axially by shoulder regions (5) provided with grooves (7). This tread (1) comprises, in central region (6), narrow groove (61) and, between each shoulder region (5) and the central region (6), an intermediate region (4) in which there are formed a plurality of oblique or transverse narrow grooves (411, 412). Narrow groove (61) of the central part is made up of first narrow-groove parts (611) of depth (P1) and of second narrow-groove parts (612) of depth (P2). Depth (P1) is greater than depth (P2). Narrow grooves (411, 412) of one same intermediate region comprise, in the circumferential direction, an alternation of narrow grooves (411) of first depth (P11) and of narrow grooves (412) of second depth (P22).

A tire tread for a heavy-duty vehicle which when new, has a maximum thickness of material to be worn away during running, a tread surface, side faces, a middle region (RM), this tread provided with tread pattern elements having channels, sipes, radial openings and blocking devices, the channels arranged in the tread and connected to the tread surface by radial openings arranged alternating with the blocking devices along the channels, where the tread is devoid of a circumferential groove, the channels arranged below the tread surface when the tread is new, the channels are transverse channels and connect RM to the side faces; each channel connecting the middle region to a side face has a direction change between RM and the side face; and maximum longitudinal distance between points of a transverse channel furthest apart in longitudinal direction is between 10% and 50% of the width of the tread (Lbdr).