A tire includes a tread portion. The tread portion has a main groove extending continuously in a tire circumferential direction, and a land portion adjacent to the main groove. The land portion has lateral grooves extending from the main groove in a tire axial direction. Each of the lateral grooves has a first portion communicating with the main groove, and a second portion connected to the first portion. The first portion has a larger groove width than the second portion and has a smaller groove depth than the second portion.

In a tire tread pattern, inclined grooves extend from a starting end in a center region including an equator toward both sides in a width direction and toward the same side in a circumferential direction to a pattern end. A periphery distance from the equator to the pattern end at an outer side in the width direction being 100%, in ranges separated from the starting end by ≤35%, from >35% to ≤50%, from >50% to ≤70% and from >70% to ≤100%, an inclination angle of the inclined grooves relative to the circumferential direction is from >40° to ≤50°, from >50° to ≤65°, from >65° to ≤80°, and from >80° to ≤90°, respectively. A circumferential-direction distance from the starting end to a terminating end of the inclined grooves is 60% to 90% of a width-direction distance.

A tire includes a main groove extending in a circumferential direction, a lug groove extending in a width direction, a land portion defined by the main groove and the lug groove, and a sipe that is a narrow groove that is formed in the land portion, extends in the width direction, and includes an end opening to the main groove. The lug groove includes a raised bottom portion formed in a central region of the land portion in the width direction. The sipe includes shallow and deep bottom portions having different depths from a tread contact surface. A deep bottom portion depth from the tread contact surface is greater than a shallow bottom portion depth and includes at least a part disposed in the central region. The raised bottom portion and the deep bottom portion are disposed overlapping each other in the circumferential direction.

A tire comprises a tread portion having an outboard tread edge To and an inboard tread edge Ti. The tread portion is provided with: an outboard shoulder main groove extending continuously in the tire circumferential direction; an outboard crown main groove extending continuously in the tire circumferential direction and disposed between the outboard shoulder main groove and a tire equator; and outboard lateral grooves extending from the outboard crown main groove to the outboard tread edge To. The groove width of each of the outboard lateral grooves is decreased toward the outboard crown main groove 4.

Heavy load pneumatic radial tire according to the present invention includes: tread rubber 6 having laminated structure of cap rubber 5 and base rubber 4; and four or more belt layers 3a-3e disposed radially inward of tread rubber 6. A radially outer side of a width direction side edge of at least one of radially outermost belt layer 3e and widest-width belt layer 3c is covered by reinforcing rubber layer 7 that terminates on a radially inner side of tread rubber 6 without reaching tire equatorial plane E. Relative relation between reinforcing rubber constituting reinforcing rubber layer 7 and base rubber 4 in terms of modulus of rebound elasticity satisfies the condition: reinforcing rubber<base rubber 4.

A tire includes a tread portion provided with a plurality of blocks. At least one of the plurality of blocks is provided with a sipe. The sipe extends in a sipe longitudinal direction to form a zigzag opening configuration on a ground contact surface of the at least one of the plurality of blocks. The sipe extends inwardly in a tire radial direction such that the zigzag opening configuration oscillates in the sipe longitudinal direction repeatedly with a total amplitude and a wavelength while maintaining the zigzag opening configuration. A half of the wavelength of the sipe is in a range of from 0.10 to 0.24 times a maximum depth of the sipe, and a slope of the half of the wavelength with respect to the total amplitude has an angle in a range of from 45 to 65 degrees.

A tire tread formed from a rubber composition having a functionalized SBR and a BR that is reinforced with between 95 phr and 125 phr of a silica filler and includes a plasticizing system to adjust the glass transition temperature to be between −30° C. and −15° C. and the dynamic modulus G* at 60° C. to be between 0.9 MPa and 1.15 MPa. The tread includes central tread blocks having an average central tread block length of between 6.5 mm and 10 mm and shoulder tread blocks having an average shoulder tread block length of between 10 mm and 20 mm. Furthermore the tread is limited to being between 6.5 mm and 7.7 mm thick. In particular embodiments the rubber composition may be just the functionalized SBR.

A pneumatic tire comprises in a tread surface thereof a land portion that comprises a plurality of blocks. Each of the blocks comprises in a contact patch thereof a plurality of narrow shallow grooves and a plurality of recessed portions disposed separated from the narrow shallow grooves. The narrow shallow grooves have a groove width of from 0.2 mm to 0.7 mm and a groove depth of from 0.2 mm to 0.7 mm. The recessed portions have the same depth as the narrow shallow grooves.

Provided is a pneumatic radial tire for a passenger car that exhibits both riding comfort at low temperatures and stealing stability at high-speed running. The present invention is a pneumatic radial tire for a passenger car, in which: a carcass and a tread are provided; the tread is integrated into a standardized rim; when internal pressure is at a standardized internal pressure, the tire has a cross-sectional width Wt (mm) and an outer diameter Dt (mm) satisfying 1963.4≤(Dt.sup.2π/4)/Wt≤2827.4; the tread comprises at least one main groove in a running surface of the tread, extending in the circumferential direction of the tread; the land/sea ratio at the tread running surface is greater than 55% and less than 85%; and a rubber composition that forms the tread has a loss tangent (tan δ) which, when measured at a frequency of 10 Hz, an initial strain of 2%, and a dynamic strain rate of 1%, is such that |20° C. tan δ-50° C. tan δ| is at least 0.01 and less than 0.15, and 15° C. tan δ-20° C. tan δ| is greater than 0.15 and less than 0.70.

A tire includes a plurality of circumferential main grooves extending in a tire circumferential direction, and a pair of shoulder land portions and one or more rows of center land portions defined by the plurality of circumferential main grooves. Further, at least one of the pair of shoulder land portions includes a plurality of shoulder lug grooves and a plurality of shoulder blocks defined and formed by the plurality of shoulder lug grooves. Additionally, at least a part of the plurality of shoulder blocks includes a notch portion that connects edge portions separated from a tire ground contact edge and a buttress portion. Additionally, the notch portion has a step-shaped wall surface in a cross-sectional view in a tire meridian direction.