A tire includes a tread portion including first to third main grooves continuously extending in a tire circumferential direction. The first main groove has a groove centerline arranged on a side of the inboard tread edge with respect to a tire equator and the groove centerline is located at an axial distance L1 from the tire equator of from 5% to 25% of a tread half width. The second main groove is arranged between the first main groove and the inboard tread edge and has a groove centerline located at an axial distance L2 from the tire equator of from 35% to 65% of the tread half width. The third main groove is arranged between the tire equator and the outboard tread edge and has a groove centerline located at an axial distance L3 from the tire equator of from 25% to 55% of the tread half width.

A pneumatic tire is provided with, in the tread surface, land portions that include a rib or a plurality of blocks. The land portions are provided with a plurality of narrow shallow grooves and a plurality of recessed portions in a contact patch. The opening area ratio Se of the recessed portions in the end portion regions in the tire lateral direction of one continuous contact patch and the opening area ratio Sc of the recessed portions in the central portion region in the tire lateral direction have the relationship Sc<Se, where the central portion region is defined as the region in the central portion in the tire lateral direction occupying 50% of the continuous contact patch of the land portions, and the end portion regions are defined as the regions in the left and right end portions in the tire lateral direction occupying 25%.

A pneumatic tire has a tread having adjacent rib-shaped land portions (4) with circumferential grooves (3) therebetween. Annular elongate projection portions (5, 5) project toward each other from adjacent rib-shaped land portions (4). The elongate projection portions (5, 5) confronting each other are disposed with a spacing therebetween such that their mutually confronting tip surfaces (5s, 5s) make contact with each other due to elastic deformation of the rib-shaped land portions (4, 4) at the time of grounding of the tire. An inside groove space (6) is formed on a radially inner side of the confronting elongate projection portions (5, 5) and an outside groove space (7) is formed on a radially outer side of the elongate projection portions (5, 5). The tip surfaces (5s) of the elongate projection portions (5) are formed with a plurality of communication recesses (9) providing communication between the inside and outside groove spaces (6, 7). The communication recesses (9) are formed at intervals in a tread circumferential direction. It is thus possible to enhance rigidity of the rib-shaped land portions over the whole tread at the time of grounding of the tire, thereby to suppress elastic deformation of the rib-shaped land portions and to reduce rolling resistance, while securing a draining property attributable to the circumferential grooves.

Provided is a pneumatic motorcycle tire in which, without compromising the stability during running, other performances such as light-weight are improved. Provided is a pneumatic motorcycle tire which comprises a tread portion 1, and side wall portions 2 and bead portions 3 extending from both sides of the tread portion, and whose rotation direction when the tire is mounted on a vehicle is designated. A tire tread is provided with a bent main groove composed of: a first groove 11 extending toward the designated tire rotation direction inclined outside in the tread width direction in a contact region during straight running; a second groove 12 extending from the end portion of the first groove in the reverse rotation direction of the designated tire rotation direction toward the reverse rotation direction of the designated tire rotation direction inclined outside in the tire width direction; and a third groove 13 extending from the end portion of the second groove in the reverse rotation direction of the designated tire rotation direction toward the reverse rotation direction of the designated tire rotation direction inclined outside in the tire width direction, and the bent main groove is formed such that an inclination angle .sub.3 with respect to the tire circumferential direction of the third groove is larger than an inclination angle .sub.2 with respect to the tire circumferential direction of the second groove.

Provided is a pneumatic tire including a tread portion, sidewall portions, and bead portions. The tread portion comprises a center main groove extending in the tire circumferential direction and a shoulder main groove located outward of the center main groove and extending in the tire circumferential direction. A land portion is defined between the center main groove and the shoulder main groove. The center main groove has a zigzag shape in the tire circumferential direction. Lug grooves extending inward from the shoulder main groove in the tire lateral direction and terminating without communicating with the center main groove are provided in the land portion. A bent portion bent toward a first side in the tire circumferential direction is formed at a terminating end of each of the lug grooves. Narrow grooves extending discontinuously in the tire circumferential direction without communicating with the bent portions are formed in the land portion.

A pneumatic tire includes: a zigzag circumferential direction groove that is formed in a tread portion by alternating and continuously formed first inclined portions and second inclined portions, the first inclined portions being inclined with respect to a tire circumferential direction and the second inclined portions being inclined in the opposite direction to the first inclined portions with respect to the tire circumferential direction; first lug grooves that are inclined in the same direction as the first inclined portions with respect to the tire circumferential direction and that merge with the first inclined portions; and second lug grooves that are inclined in the opposite direction to the first inclined portions with respect to the tire circumferential direction and that intersect the first inclined portions.

A motorcycle pneumatic tire includes a tread portion including a crown region, a pair of middle regions and a pair of shoulder regions upon a tread development width of the tread portion being divided equally into five regions. The tread portion is provided with a pair of circumferentially and continuously extending crown main grooves within the crown region to include a tire equator therebetween and a plurality of inclined grooves each extending from the crown region to the shoulder region in each side of the tire equator without communicating with the crown main grooves. Each of the inclined grooves includes a straight portion extending straightly in the middle region and an arc portion extending in an arc shape in the shoulder region while increasing an angle with respect to a circumferential direction of the tire axially outwardly.

The pneumatic tire according to the present technology includes a tread portion, sidewall portions, and bead portions, and has a designated mounting direction on a vehicle. The pneumatic tire is provided, in the tread portion, with four main grooves including a pair of center main grooves extending in the tire circumferential direction and a pair of shoulder main grooves located outside the center main grooves and extending in the tire circumferential direction; these main grooves define five rows of land portions; the center main groove on the vehicle outer side has a zigzag shape in the tire circumferential direction; and a plurality of lug grooves extending from the main grooves, except the center main groove having a zigzag shape, toward both sides in the tire lateral direction and terminating in the land portions are provided in the tread portion.

It is described a motorcycle tyre (100) intended to be fitted to a wheel of a motorcycle of the supersport segment, comprising an equatorial plane and a tread band extending in axial direction with a given axial development, wherein the tread band comprises a first annular portion made of a first elastomeric material, having a first dynamic shear storage modulus measured at 70? C., and at least one second annular portion made of a second elastomeric material, having a second dynamic shear storage modulus measured at 70? C., different form said first dynamic shear storage modulus measured at 70? C.

Tread (1) for a tire of a heavy-duty vehicle, having a tread surface (10), this tread (1) comprising, near to each of its edges (11), a plurality of open wells (2) on the tread surface when new, these open wells (2) of depth Pmax being arranged circumferentially with a mean distance D between two consecutive open wells; each open well (2) being delimited by two main faces (21, 22) facing one another, this tread being such that each open well (2) is connected to at least one hidden cavity (32) formed within the tread, this hidden cavity (32) opening into a main face (21, 22) of said well.