A pneumatic tire includes a tread portion being provided with at least one circumferentially and continuously extending main groove and at least one land portion adjacent to the main groove. The land portion includes a corner portion formed between a ground contact surface and a sidewall of the land portion on the side of the main groove. The land portion is provided with a lug groove extending from the main groove and terminating within the land portion. The corner portion includes a chamfered portion and a non-chamfered portion. The chamfered portion includes a first end in communication with the lug groove.

A radial tire intended to be fitted to a heavy vehicle of construction plant type, and more particularly to the tread thereof. The tread of such a tire is desensitized to attack by indenting bodies that are likely to cause cracks at the cut bottom, in particular in the case of a tread with a high volumetric void ratio and a high degree of surface siping. Such a tire has a degree of surface siping TL of the tread at least equal to 3 m/m.sup.2, a number of cycles to failure N.sub.R of the elastomeric compound of the tread, at least present at the cut bottom, at least equal to 60000 cycles, and a ratio C between the number of cycles to failure N.sub.R of the elastomeric compound and the degree of surface siping TL at least equal to 20000 cycles/(m/m.sup.2).

A pneumatic tire is provided with an asymmetrical tread pattern. The width of an outboard shoulder main groove is less than the width of an outboard crown main groove. The angle of the axially inner groove-sidewall is less than that of the axially outer groove-sidewall. An outboard shoulder land region is provided with outboard shoulder blind grooves extending from the outboard tread edge and terminating within the outboard shoulder land region, and outboard shoulder lateral grooves extending from the outboard tread edge to the outboard shoulder main groove, which are arranged alternately in the tire circumferential direction. An outboard middle land region is provided with outboard middle blind grooves extending axially inwardly from the outboard shoulder main groove, and outboard middle sipes extending from inner ends of the outboard middle blind grooves to the outboard crown main groove.

The tread includes over at least a first axial part (M) at least one wavy groove in a first direction and wavy grooves in a second direction. The wavy grooves in the second direction are connected to the wavy groove in the first direction. Over at least a second axial part (B) of the tread, at least one wavy groove continuous in a third direction, and wavy grooves continue in a fourth direction. The wavy grooves in the fourth direction are connected to the wavy groove in the third direction. When new, the open parts of the first axial part (M) are connected to one another, and the open parts of the second axial part (B) are not connected with one another. Beyond a part-wear condition, the open parts of the second axial part (B) are connected to one another, and the open parts of the first axial part (M) are not connected with one another.

The present invention concerns a tire (10) comprising a tread (11) provided with a base surface (14) and with a plurality of ribs (12), each rib (12) being provided with a front wall and a rear wall, and a shaped profile (15), wherein the shaped profile (15) has a section that defines at least one flat surface (17) of the shaped profile (15) which is parallel, or inclined at an angle up to 20, to the surface of the head (16) of the rib and which is joined to the front wall of the rib (12) by means of a connecting surface (18), at least one sharp angle (19) of the shaped profile (15) and at least one front wall (23) of the shaped profile (15), which is joint to the base surface (14) of the tread (11) by means of a connecting surface (21).

A pneumatic tire, having in a ground contact surface of a tread a plurality of main grooves extending in the tread circumferential direction and a plurality of land portions demarcated by the main grooves and tread ends, wherein, provided that two land portions adjacent to the central land portion on the respective sides in the tread width direction of the central land portion each represent an adjacent land portion, rigidity in the tread circumferential direction of the central land portion is lower than rigidity in the tread circumferential direction of the adjacent land portion.

A pneumatic tire comprises a tread portion 2 provided with two shoulder main grooves 3, a crown main grooves 4, two shoulder land zones 8, and two middle land zones 7. The shoulder land zones 8 are each provided with shoulder lateral grooves 11. The middle land zones 7 are each provided with middle narrow grooves 10. Each of the middle narrow grooves 10 comprises a sipe-like narrow portion 12 whose groove width is less than 2 mm, and a wide portion 14 whose groove width is not less than 2 mm. The wide portion 14 includes an axially outer wide portion 15 formed at the axially outer end of the middle narrow groove 10.

A sipe is provided to a land portion provided to a tread of a pneumatic tire. The sipe is formed of a wide portion having a groove width W1 and a narrow portion having a groove width W2 narrower than the groove width W1. The wide portion extends in a sipe depth direction D at both ends in a sipe length direction L and extends in the sipe length direction L at an upper end in the sipe depth direction D. The narrow portion is surrounded by the wide portion on three sides including both sides in the sipe length direction L and an opening side in the sipe depth direction D and extends to a sipe bottom. Consequently, chipping of rubber is suppressed by reducing pulling resistance of a sipe plate at the time of die releasing of a tire while suppressing breakage of the sipe plate.

A motorcycle tyre for traveling on rough terrain, the tyre includes a tread portion provided with blocks. The at least one of the blocks includes a ground contact surface having a pair of lateral edges extending in a tyre axial direction. The at least one of the blocks is provided with a pair of lateral narrow grooves extending in the tyre axial direction on the ground contact surface to form a pair of edge-side portions defined between the pair of lateral narrow grooves and the pair of lateral edges. The at least one of the pair of edge-side portions includes a neck portion having a minimum circumferential length thereof, wherein a circumferential length of the at least one of the pair of edge-side portions increases toward axially both sides from the neck portion.

A pneumatic tire includes a block (41) formed by being partitioned by a main groove (15) and lateral grooves (20 and 25), and a block traversing sipe (45) which is a sipe longitudinally traversing the block (41), in which the block traversing sipe (45) has a zigzag shape that is constituted by a plurality of longitudinal sipe portions (42) extending in a circumferential direction of the tire, and a lateral sipe portion (43) extending in a tire width direction and connecting end portions of two longitudinal sipe portions (42), and a longitudinal sipe portion (42) closer to a kick-out side of the block (41) has a narrower width.