A tire comprises a tread portion whose shoulder land part is provided with a narrow circumferential groove having an axially inner wall surface, an axially outer wall surface and a groove bottom including a deepest point. The axially inner wall surface has a radially inner curved portion concaved toward the axially inside, and the axially outer wall surface has a radially inner curved portion concaved toward the axially outside. the radially outer end of the radially inner curved portion of the axially inner wall surface is positioned radially inside the radially outer end of the radially inner curved portion of the axially outer wall surface.

A tyre includes a tread portion being provided with at least one main groove extending in a tyre circumferential direction and at least one lateral groove connected to the at least one main groove. The at least one main groove includes an intersection to which the lateral groove is connected. One of groove walls of the at least one main groove or the at least one lateral groove is provided with projections protruding toward the intersection.

A tire includes a pair of sidewalls and a circumferential tread having a zigzag circumferential groove. The zigzag circumferential groove is defined by a groove bottom, a pair of groove walls, and a pair of groove edges defining an intersection between each groove wall and a top surface of the circumferential tread, wherein each of the groove edges smoothly widens and narrows along the groove. The circumferential tread has a first circumferential pitch with first and second circumferential pitch lengths. The first circumferential pitch includes a first zigzag circumferential groove segment and a second zigzag circumferential groove segment that form a first intersection angle. The second circumferential pitch includes a third zigzag circumferential groove segment and a fourth zigzag circumferential groove segment that form a second intersection angle different from the first intersection angle.

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.

A tire comprises a tread portion 2 comprising a shoulder main groove 5 extending on a side of a tread edge (Te). The shoulder main groove 5 comprises an inner groove wall 11 having an angle with respect to its tread normal line in a cross section of the shoulder main groove 5 periodically increasing and decreasing in a tire circumferential direction so that the inner groove wall 11 comprises concave wall portions 16 and convex wall portions 17 arranged alternately in the tire circumferential direction. The concave wall portions 16 are provided at inner end portions thereof in a tire axial direction with recess portions 20 locally recessed inwardly in the tire axial direction and having openings at a ground contacting surface of the tread portion 2.

A tire includes a tread portion being provided with a crown main groove extending continuously in a zigzag manner in a tire circumferential direction and a shoulder main groove extending continuously in a zigzag manner in the tire circumferential direction. The shoulder main groove is arranged outwardly of the crown main groove in a tire axial direction. The crown main groove has a number of zigzag pitches in a range of from 0.21 to 0.32 times a number of zigzag pitches of the shoulder main groove.

The on-ice performance of the tire is improved while the tipping of the block in the tread portion is suppressed. The tire comprises a block (31) in the tread portion. The side wall (35) of the block (31) extends along the tire circumferential direction (S) between both end walls (36) in the tire circumferential direction (S). The central sipe (22) of the block (31) is formed along the tire width direction (H) on the block tread (34) of the block central portion (33) in the tire circumferential direction (S), and opens at the side wall (35). The side wall angle (P) between the tire radial surface (K1) and the side wall (35) of the block (31) increases from the block central portion (33) toward the end wall (36).

Provided is a tire including, in a tread surface, a plurality of land portions partitioned by a circumferential main groove extending continuously in a tire circumferential direction on at least one side in a tire width direction, and comprising, in an internal land portion located in a vehicle-installed inside half portion to a tire equator plane among the plurality of land portions, a resonator including an auxiliary groove that terminates in the internal land portion, and a branch groove that communicates between the auxiliary groove and the circumferential main groove, and a hidden groove having an opening width in the tread surface that is smaller than a groove width of a groove bottom is provided in at least a part of the auxiliary groove.

A tyre includes a tread portion being provided with two circumferential grooves extending in a tyre circumferential direction to form a crown land portion therebetween. The crown land portion is provided with two or more crown grooves extending inwardly of the crown land portion from the respective circumferential grooves. Each crown groove includes wide-width regions and narrow-width regions having a groove width smaller than that of the wide-width regions, and the wide-width regions and the narrow-width regions are alternated.

Provided is a tire including, in a tread surface, a plurality of land portions partitioned by a circumferential main groove extending continuously in a tire circumferential direction, on at least one side in a tire width direction, and comprising, in an internal land portion located in a vehicle-installed inside half portion to a tire equatorial plane among the plurality of land portions, an internal resonator including a first auxiliary groove that terminates in the internal land portion, and a first branch groove that communicates between the first auxiliary groove and the circumferential main groove, and in the first branch groove, a hidden groove having an opening width in the tread surface that is smaller than a groove width of a groove bottom is provided adjacent to the first auxiliary groove.