A pneumatic tire comprises a tread surface of a tread portion comprising land portions defined by three circumferential grooves extending in the tire circumferential direction and main lug grooves forming intra-land portions divided in the tire circumferential direction; the intra-land portions being divided by the laterally outer circumferential grooves, the main lug grooves, and circumferential narrow grooves to form long small land portions, which are long in the tire circumferential direction); and the intra-land portions being divided by the laterally central circumferential groove, the main lug grooves, subsidiary lug grooves, and the circumferential narrow grooves to form two short small land portions, which are short in the tire circumferential direction.

A pneumatic tire comprises a tread surface comprising main grooves extending in a tire circumferential direction, at least two of the main grooves adjacent in the tire circumferential direction having a wave shape with periodic oscillation; adjacent land portions in a tire lateral direction formed by the main grooves; lug grooves disposed in a row in the tire circumferential direction in the land portion formed between the wave-shaped main grooves, the lug grooves intersecting the tire circumferential direction and communicating with the wave-shaped main grooves at both ends; and narrow grooves disposed between pairs of the lug grooves adjacent in the tire circumferential direction in a row in the tire circumferential direction, the narrow grooves intersecting the tire circumferential direction, communicating with one of the main grooves at a first end, terminating within the land portion at a second end, and having a narrower groove width than the lug grooves.

A pneumatic tire includes circumferential main and narrow grooves, shoulder and second land portions, and closed lug grooves. The circumferential main groove is in a region outer side in a width direction demarcated by an equatorial plane. The circumferential narrow groove is outward of the circumferential main groove in a width direction. The shoulder and second land portions are defined by the circumferential main and narrow grooves. The closed lug grooves extend in the width direction and penetrate the circumferential narrow groove. The closed lug grooves have inner terminating end portions in the width direction inside the second land portion and have outer terminating end portions inside the shoulder land portion. An extension length L1_min in the width direction of the shortest first closed lug grooves and an extension length L1_max in the width direction of the longest second closed lug grooves have a relationship 1.10L1_max/L1_min3.00.

A tire comprises a tread portion provided with a first middle main groove, a second middle main groove, a crown longitudinal groove disposed between the first middle main groove and the second middle main groove, first crown lateral grooves connecting between the crown longitudinal groove and second middle main groove, and second crown lateral grooves connecting between the crown longitudinal groove and the second middle main groove. The first crown lateral grooves and the second crown lateral grooves are arranged so as to be misaligned with each other in the tire circumferential direction. The crown longitudinal groove is provided with at least one crown tie bar formed by raising a groove bottom of the crown longitudinal groove.

A tire (1) for a motorcycle comprises a tread portion (2) comprising main grooves (3) and narrow grooves (4). The main grooves (3) include first main grooves (5) and second main grooves (6) arranged on an axially outer side of the first main grooves (5). The narrow grooves (4) include open narrow grooves (7) and semi-open narrow grooves (8). Each of the open narrow grooves (7) is arranged such that one end (7a) is substantially connected with respective first main groove (5) and the other end (7b) is substantially connected with respective second main grooves (6). A first end (8a) of each of the semi-open narrow grooves (8) is substantially connected with one of the first main grooves (5) or the second main grooves (6). A second end (8b) of each of the semi-open narrow grooves (8) terminates on a ground contacting surface (2a) of the tread portion (2).

A pneumatic tire includes a main groove in a tread portion. The main groove has a groove depth of from 7 mm to 11 mm. A rubber composition for a tread constituting the tread portion includes a natural rubber, a styrene-butadiene rubber, and a butadiene rubber as a rubber component. The average glass transition temperature of the rubber component is 50 C. or lower. Silica is compounded in the rubber composition for a tread at 50 parts by mass to 100 parts by mass per 100 parts by mass of the rubber component. The compounded amount of the silica is 80 mass % or more of the total amount of carbon black and silica. Aroma oil is compounded in the rubber composition for a tread at 40 mass % or less relative to the amount of silica.

A pneumatic tire includes lug grooves having alternating first and second groove portions. The first groove portion intersects an equator, extends in a width direction, and communicates with an adjacent second groove portion. The second groove portion inclines from the first groove portion at a smaller angle relative to a circumferential direction smaller than that of the first groove portion and extends to a tread edge on one side. The first groove portion is on a stepping side with respect to an end on the tread edge side. The second groove portions curve or bend and have an average angle in an inner region smaller than that of the second groove portions in an outer region. A maximum length in the width direction of center blocks defined by narrow grooves connecting adjacent second groove portions and the lug grooves is 25%-35% of a development width.

In a pneumatic tire, an inner second land portion includes chamfered portions and lug grooves. The chamfered portions are on an edge portion on a tire ground contact edge side of the inner second land portion and widen chamfer widths on a road contact surface of the inner second land portion in a tire circumferential direction. The lug grooves terminate in the inner second land portion at one end portion and open to central portions in a longitudinal direction of the chamfered portions at another end portion. An outer second land portion and an outer shoulder land portion include closed lug grooves terminating in the outer second land portion at one end portion. The closed lug grooves extend in the tire width direction and penetrate a circumferential narrow groove. The closed lug grooves terminate in a ground contact surface of the outer shoulder land portion at another end portion.

A tire has cap rubber that forms a contact patch. The cap rubber has a plurality of lugs. A shoulder lug, which among the plurality of lugs is that which is located outwardmost in a tire width direction, has a narrow groove that extends in the tire circumferential direction and that partitions the shoulder lug into a main lug portion toward the interior in the tire width direction, and a sacrificial lug portion toward the exterior in the tire width direction; and low-modulus rubber, for which stress at a given elongation is lower than that of the cap rubber, is arranged at a corner where the contact patch at the main lug portion and a groove side face toward the interior in the tire width direction which forms the narrow groove intersect.

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.