A tire vulcanization mold including a sector mold divided into a plurality of pieces along a circumferential direction of a green tire, the sector mold configured to vulcanization mold a tread portion of the green tire into a predetermined shape, and an upper mold and a lower mold disposed on both sides of the green tire so as to sandwich the green tire therebetween in an axial direction of the green tire, the upper mold and lower mold configured to vulcanization mold a side portion of the green tire into a predetermined shape. The sector mold has a weir portion in a vicinity of a fitting portion between the sector mold, and the upper mold and the lower mold.

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.

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.

An asymmetrical tire is provided that includes at least a crown, a first shoulder having a first tread, and a second shoulder having a second tread. In one embodiment of the present invention, the crown and second shoulder include high-performance tread and the first shoulder includes off-road tread. By using off-road tread on the outer shoulder, the tire will have the visual aesthetics of an off-road tire. And by using high-performance tread on the crown and second shoulder, the vehicle will exhibit a smooth and quiet ride that is fuel efficient, and will not rub on, or interfere with the vehicle's wheel well or splash guard. In one embodiment, an upper portion of the first shoulder includes high-performance tread and a side portion includes off-road tread. By using two different types of tread on the outer shoulder, the tire can provide a smoother ride, while still exhibiting an off-road appearance.

A pneumatic tire comprises a tread portion with a tread surface; four main grooves in the tread surface of the tread portion, extending in a tire circumferential direction; and a center land portion, middle land portions adjacent to the center land portion on either side in a tire lateral direction, and shoulder land portions outwardly adjacent to the middle land portions in the tire lateral direction formed by the main grooves. The main grooves have a wave-like shape with a constant groove width in the tire circumferential direction and with periodic oscillation.

A heavy duty tire 10 includes a recess portion 34, a circumference-direction air entry and exit promotion portion 36 and an air-catching wall portion 42. The recess portion 34 is formed in a buttress portion 26 and opens to a tire outer side. The circumference-direction air entry and exit promotion portion 36 is disposed at one side of a floor portion 40 in a tire rotation direction and includes a slope 46 that, from the floor portion 40 toward a tire surface, gradually decreases in depth from the tire surface. The circumference-direction air entry and exit promotion portion 36 facilitates access of air toward the floor portion. The air-catching wall portion 42 is disposed at the opposite side of the floor portion 40 from the circumference-direction air entry and exit promotion portion 36. The air-catching wall portion 42 has a greater angle relative to the tire surface than the slope.

In a tire 2 according to the present invention, an outer surface 52 of a crown rib 48e and an outer surface 54 of a shoulder rib 48s form a part of a tread surface 28. On a cross-section of the tire 2 along a plane that includes a rotation axis of the tire 2, an outline of the outer surface 52 of the crown rib 48e is represented as a first arc. A center of a circle to which the first arc belongs is disposed on the equator plane. An outline of the outer surface 54 of the shoulder rib 48s is represented as a second arc. A ratio of a distance from a center of a chord of the second arc to the second arc relative to a length of the chord of the second arc is not less than 0.03 and not greater than 0.05.

In a pneumatic tire, at least one of plurality of projecting portions includes at least one opening. At least one of the projecting portions is divided into an inner region placed on the inner side in a tire radial-direction and an outer region placed on the outer side in the tire radial-direction with respect to a position of an outer end of a belt play in a tire width-direction, the belt play placed on the innermost side in the tire radial-direction. A depth of the opening in the inner region is different from a depth of the opening in the outer region.

In a tire having composite grooves provided on a shoulder land portion, dry performance and wet performance are improved. The tire includes a tread portion 2. The tread portion 2 includes a first shoulder land portion 13. The first shoulder land portion 13 has shoulder lateral grooves 15 and shoulder composite grooves 20. The shoulder lateral grooves 15 and the shoulder composite grooves 20 are each curved so as to be convex in a tire circumferential direction. Each shoulder composite groove 20 includes, in a cross section thereof, a sipe element 21 having a width not greater than 1.5 mm and extending from a tread surface of the first shoulder land portion 13 in a tire radial direction, and a groove element 22 connected to an inner side in the tire radial direction of the sipe element 21 and having a width greater than 1.5 mm.

In a tire having a composite groove provided on a shoulder land portion, the durability of the shoulder land portion is improved. The tire includes a tread portion. The tread portion includes a first shoulder land portion including a first tread edge. The first shoulder land portion has a shoulder composite groove, and a recess formed on a buttress surface. The recess includes an opening edge on the buttress surface, a bottom surface along the buttress surface, and an inner wall surface connecting the opening edge to the bottom surface. The shoulder composite groove includes, in a transverse cross section thereof, a sipe element having a width not greater than 1.5 mm and extending in a tire radial direction, and a groove element connected to an inner side in the tire radial direction of the sipe element and having a width greater than 1.5 mm. The groove element is open at the bottom surface of the recess.