A tire includes a tread portion provided with a first main groove disposed between the tire equator and a tread edge and extending continuously in the tire circumferential direction; outward transverse grooves extending axially outwardly from the first main groove; and inward transverse grooves extending axially inwardly from the first main groove. The first main groove is a zigzag groove including axially outer segments extending along the tire circumferential direction; axially inner segments extending along the tire circumferential direction and positioned axially inside the axially outer segments; and oblique segments linking therebetween. Each of the axially outer segments is connected with one of the outward transverse grooves and one of the inward transverse grooves.

The present technology provides a heavy duty pneumatic tire with a tread portion having a tread pattern including: a pair of circumferential primary grooves defined in a wave-like shape and extending in the tire circumferential direction; center lug grooves; center blocks; and circumferential secondary grooves extending in regions of the center blocks and open to the center lug grooves. The center lug grooves have two groove turning portions turned in a bend shape or a curved shape. The circumferential secondary grooves extend in an inclined manner relative to the tire circumferential direction. An inclination angle (θ.sub.4) of the circumferential secondary grooves relative to the tire circumferential direction is different from an inclination angle (θ.sub.1) of portions of the circumferential primary grooves relative to the tire circumferential direction, the portions extending toward the same side as a side in the tire width direction, toward which the circumferential secondary grooves are inclined.

A pneumatic tire includes circumferential grooves aligned in a lateral direction and extending in a circumferential direction, lateral grooves aligned in the circumferential direction and extending to cross the circumferential direction, communicating at ends with the circumferential grooves and defining a block-shaped land portion between the circumferential grooves, two narrow grooves aligned in the lateral direction and extending in the circumferential direction, communicating at ends with a lateral groove and dividing the land portion defined by each of the circumferential grooves and each of the lateral grooves into small land portions, the narrow grooves having a smaller groove width than the circumferential grooves and being formed with a bent portion in an intermediate portion, the bent portion being disposed inward in the lateral direction, and bend points of the bent portions being disposed at positions offset from one another in the circumferential direction.

A pneumatic tire includes first and second main grooves, and first sipes and auxiliary grooves on second land portions between the first and second main grooves, the auxiliary grooves opening to the second main grooves and terminating in the second land portions. The auxiliary grooves bend at a bend point and include a first portion extending from an opening end to the bend point, and a second portion extending from the bend point to a terminating end. A groove width of the first portion gradually reduces from the opening end to the bend point. Second sipes have an end that opens to each of the second main grooves and another end that opens to each of the terminating ends. Third sipes have an end that opens to the first main grooves and another end that opens to the first portions. The sipes are parallel to each other.

A center rib is formed by two circumferential main grooves. A main inclined groove and an auxiliary inclined groove are formed in the center rib. The main inclined groove is inclined with respect to the tire circumferential direction to become distanced from the tire equatorial plane from a leading side toward a trailing side in a tire rotational direction, a plurality of the main inclined grooves being juxtaposed in the tire circumferential direction and disposed alternately in the tire circumferential direction on both sides of the tire equatorial plane. The auxiliary inclined groove inclines with respect to the tire circumferential direction to become distanced from the tire equatorial plane from the leading side toward the trailing side in the tire rotational direction, a leading end and a trailing end terminating within the center rib while intersecting at least two of the main inclined grooves.

A pneumatic tire comprises a tread portion 2 provided with shoulder axial grooves 10 extending from a shoulder main groove 3 to a tread edge Te while inclining to a first-side in the tire circumferential direction. The shoulder axial groove 10 has a first-side groove edge, a second-side groove edge, a first-side groove-sidewall 14 extending radially inward from the first-side groove edge 12, and a second-side groove-sidewall 15 extending radially inward from the second-side groove edge 13. The shoulder axial groove 10 has a part where the inclination angle β of the first-side groove-sidewall 14 with respect to a normal line passing through the first-side groove edge 12 perpendicularly to the tread surface 2s is more than the inclination angle α of the second-side groove-sidewall 15 with respect to a normal line passing through the second-side groove edge 13 perpendicularly to the tread surface 2s.

A tire is a tire in which circumferential grooves, and lug grooves comprising opening portion in tread end and which extend in the tread width direction from the tread end to the circumferential groove, are formed. Projection parts are provided in the groove bottom of the circumferential grooves. The projection parts extend from one side wall forming a circumferential groove to the other side wall opposite the one side wall. Multiple lug grooves are formed at predetermined intervals in the circumferential direction. In the tread surface view of the tire, given points of intersection as the points at which a circumferential groove extension that passes through a circumferential groove intersects with a lug groove extension that passes through a lug groove, the projection parts are provided between a first point of intersection and a second point of intersection adjacent to the first point of intersection in the circumferential direction.

A pneumatic tire includes a tread portion provided with circumferentially extending main grooves and lateral grooves. The main grooves include an inboard shoulder main groove, an outboard shoulder main groove, an inboard center main groove and an outboard center main groove. The lateral grooves includes a plurality of first outboard shoulder lateral grooves each having an axially inner end positioned between the outboard shoulder main groove and the outboard center main groove, and a plurality of first inboard shoulder lateral grooves each having an axially inner end positioned between the inboard shoulder main groove and the inboard center main groove, wherein the number of the first inboard shoulder lateral grooves is greater than the number of the first outboard shoulder lateral grooves.

A pneumatic tire includes a tread having a shoulder main groove, and a center main groove such that the tread is divided into a shoulder land portion and a middle land portion between the shoulder main groove and center main groove. The shoulder and center main grooves are formed such that a ratio W1/W2 of a tire axial direction width W1 of the shoulder land portion to a tire axial direction width W2 of the middle land portion is in range of 6 to 2.4. The shoulder land portion has a shoulder narrow groove formed on a shoulder main groove side and continuously extending in the tire circumferential direction such that the shoulder narrow groove has groove width smaller than groove width of the shoulder main groove, and the tread is formed such that a first camber amount is in range of 5.3% to 6.5% of tread ground contact width.

A pneumatic tire includes four main grooves defining a central land portion, intermediate land portions, and outer land portions. Compound grooves including lateral grooves communicate with the main groove and terminate inside a land portion, and including sipes extending from the lateral grooves to the main groove, are formed at an interval in the tire-circumferential direction in the central land portion or an intermediate land portion. An opening direction of the lateral grooves relative to the main grooves alternatingly reverses in the tire circumferential direction. The lateral grooves include a broad width portion that opens to the main groove and extends at a constant groove width, and a narrow width portion positioned between the broad width portion and the sipe and extends at a constant groove width narrower than the broad width portion.