A pneumatic tire comprises a tread rubber with a groove depth at a shoulder portion that comes into contact with a road surface of 10 mm or greater. A rubber composition of the tread rubber contains: 60 to 70 parts by mass of carbon black having a nitrogen adsorption specific surface area of 70 to 130 m.sup.2/g, 0.5 parts or greater by mass of sulfur, and a vulcanization accelerator per 100 parts by mass of diene rubber including 50 to 70 mass % of styrene-butadiene rubber, 20 to 30 mass % of butadiene rubber, and 10 to 30 mass % of natural rubber. The diene rubber has an average glass transition temperature of −65° C. or lower. A ratio of a compounded amount of the vulcanization accelerator to a compounded amount of the sulfur is 1.0 to 1.3. The tread rubber has a rubber hardness of 65 to 70 at 20° C.

A tire comprising a tread part, wherein a ratio (G/W.sub.L) of a tire weight G (kg) with respect to a maximum load capability W.sub.L (kg) of the tire is 0.0131 or less, the tread comprises at least one rubber layer composed of a rubber composition comprising a rubber component and a reinforcing filler, tan δ at 30° C. (30° C. tan δ) of the rubber composition is over 0.15, and complex modulus at 30° C. (E*.sub.30) of the rubber composition is less than 8.0 MPa, and a ratio (30° C. tan δ/G) of the 30° C. tan δ with respect to the G is 0.016 or more.

A pneumatic vehicle tire, in particular utility vehicle tire, having a tread (2) which has a profiling and which has at least one circumferential groove (1) which runs in encircling fashion in the circumferential direction of the pneumatic vehicle tire and is formed to a profile depth PT.

At least over part of the circumference of the pneumatic vehicle tire, at least one circumferential groove (1) has a cross section perpendicularly to the circumferential direction that is made up of at least two groove portions adjoining one another in a radial direction R of the pneumatic vehicle tire. A first groove portion (4) is symmetrical with respect to the radial direction R of the pneumatic vehicle tire. The width of said groove portion in the axial direction A of the pneumatic vehicle tire is less than 3 mm and does not vary by more than 10%. A second radially inner groove portion (5) is made wider in the axial direction A in comparison with the first groove portion (4). It has the largest cross-sectional area of all the groove portions. Its cross-sectional area is asymmetrical to the radial direction R, extends on both sides of the radial direction R and has an edge without corners in the bottom region of the circumferential groove (1).

The subject invention reveals a tire tread having a circumferential tread cap with circumferential grooves, wherein the tread cap rubber compound has a Shore A hardness from 45 to 75. Moreover, the tread comprises at least one circumferential groove reinforcement reinforcing at least a bottom portion of at least one of the grooves and comprising a groove reinforcement rubber compound, wherein the groove reinforcement rubber compound has a Shore A hardness from 70 to 100. The tread also comprises a circumferential tread base layer arranged radially inwards of the tread cap and comprising a tread base layer compound, wherein the tread base layer compound has a Shore A hardness from 15 to 60, and wherein the Shore A hardness of the tread cap compound is higher than the Shore A hardness of the tread base layer compound.

A pneumatic tire includes a pair of circumferential main grooves extending in a tire circumferential direction, and a pair of shoulder land portions and a single center land portion defined and formed by the circumferential main grooves. In addition, the center land portion includes a plurality of center narrow shallow grooves extending through the center land portion in a tire width direction. A groove depth H21 of the center narrow shallow groove is in a range 0.025≤H21/Hg≤0.150 with respect to a maximum groove depth Hg of the circumferential main groove.

A pneumatic tire comprises a tread rubber having a hardness less than 60 degrees. The tread portion comprises two shoulder circumferential grooves, two shoulder land portions, and one or more crown land portions therebetween. The shoulder land portion is divided into shoulder blocks by shoulder lateral-groove-like tread-pattern elements having a depth of not less than 50% of the shoulder circumferential groove depth. At least one of the crown land regions is divided into crown blocks by crown lateral-groove-like tread-pattern elements having a depth of not less than 50% of the shoulder circumferential groove depth. When a value obtained by dividing a ground contact area of one block by a maximum depth of the lateral-groove-like tread-pattern elements which divide the block is defined as the block area per unit depth, the block area per unit depth of the shoulder block is smaller than that of the crown block.

A pneumatic tire includes: a center main groove extending in a tire circumferential direction; a center land portion defined by the center main groove; a second land portion adjacent to the center land portion across the center main groove; and a second lug groove extending from the center main groove toward the second land portion in a tire lateral direction and defining the second land portion together with the center main groove; the center main groove including a center side edge portion corresponding to an edge portion on the center land portion side, the center side edge portion including a bent portion formed bent in a direction outwards in a groove width direction of the center main groove with an acute bend angle; and the second lug groove including an opening portion to the center main groove connected to the center main groove at a position opposing the bent portion.

Provided is a tire in which a tread half portion has a circumferential groove and land portions, an outline of a tread surface of the tread half portion includes circular arcs, the circular arc having a minimum radius of curvature is present within the outline of the land portion adjacent to a tread edge, the tread half portion has a base rubber layer, and a cap rubber layer, the base rubber layer has a lower storage modulus than the cap rubber layer, and an end of the layer in a tire width direction on a tread edge side is located in a region extending as much as 0.06 times a ground contact width of the tread half portion on each of both tire widthwise sides of a center of a tire widthwise length of an outline portion occupied by the circular arc having the minimum radius of curvature.

A heavy-duty pneumatic tire includes a tread portion including a pair of shoulder land portions. At least one of the pair of shoulder land portions is provided with a narrow groove extending continuously in the tire circumferential direction to divide the shoulder land portion into a main portion and a sacrificial rib located outward in the tire axial direction. The sacrificial rib includes a root portion in a tire radial direction with an axial width Wr, a top surface in the tire radial direction with an axial width Ws, and a ratio Wr/Ws being equal to or more than 1.0. In the shoulder land portion, a shortest distance Lw between the narrow groove and a maximum thickness line that defines a maximum thickness of the shoulder land portion measured in a normal direction to a tire cavity surface is equal to or less than 5.0 mm.

A tire 2 has a nominal aspect ratio of 65% or less. The tire 2 includes a tread 4 and a band 34. The band 34 includes a full band 42 and a pair of edge bands 44 located outward of ends of the full band 42 in a radial direction. A narrow groove 56 is formed on a shoulder land portion 54s of the tread 4. The narrow groove 56 includes an inner groove wall 62u and an outer groove wall 62s. The inner groove wall 62u includes an inner recess portion 64 recessed inward in the axial direction, on a groove bottom side. The outer groove wall 62s includes an outer recess portion 66 recessed outward in the axial direction, on the groove bottom side.