A tire, the tread of which has an underlayer and a circumferential reinforcement made up of a rubber mixture with a stiffness greater than the stiffness of the rubber mixture and the underlayer, has an outer side and an inner side. The circumferential reinforcement has a reinforcing element of tapered shape positioned in the tread pattern elements disposed axially on the outside with respect to the first or the second circumferential grooves of the tread from the outside to the inside and axially close to the circumferential groove.

An adaptive tire traction control system for motor vehicle tires for grip enhancement and rolling friction reduction. The tire surface area is radially divided into multiple zones, in the three zones configuration the tire is composed of an outer shoulder, centre and inner shoulder. The outer shoulder is equipped with a plurality of studs to increase the traction when vehicle is on icy or muddy surfaces. The centre part is made of low friction rubbers for the normal operation to increase fuel economy and lengthen the tires life, and reduced rolling noise. The inner shoulder is equipped with high grip rubber to provide better grip in case of emergency braking. In one embodiment, the tilting mechanism of the tire traction system can be connected to the anti-lock braking system (ABS). In case of emergency braking, the inner shoulder with high grip rubber is brought in contact with the ground to provide more grips.

An object of the present invention is to provide a tire having improved overall performance of grip performance during straight running and grip performance during cornering under a high-speed running condition.

As a result of intensive studies, it has been found that the above-described problem can be solved by, in a tire having a tread part in which a mounting direction to a vehicle is designated, dividing the tread part in a tire width direction and setting respective width and respective average values of a loss tangent tan δ of an inner tread rubber layer forming an end side inside the to vehicle when the tire is mounted to the vehicle and an outer tread rubber layer forming an end side outside the vehicle when the tire is mounted to the vehicle within predetermined ranges.

A pneumatic tire that specifies the tire mounting direction when mounted on a vehicle and has sufficiently improved grip performance at high-speed turning is provided in which the cap rubber layer on the outermost layer of the tread is divided in the tire width direction, the cap rubber layer located on the outside of the vehicle is formed of a rubber composition containing 25% by mass or less of styrene in the rubber component and having a glass transition temperature of −18° C. or higher, and, when the carbon black content ratio is C.sub.OUT (mass %), and the ground contact area ratio is L.sub.OUT, in the cap rubber layer located on the outside of the vehicle, and the carbon black content ratio is C.sub.IN (mass %) and the ground contact area ratio is L.sub.IN in the cap rubber layer located inside the vehicle, the following (Formula 1) and (Formula 2) are satisfied.

C.sub.IN<C.sub.OUT  (Formula 1)

0≤(C.sub.OUT×L.sub.OUT)−(C.sub.IN×L.sub.IN)  (Formula 2)

A racing tire comprising a tread having a new tread thickness of no greater than about 0.375 inch. The tread defines a running surface that includes a first circumferential portion of a first rubber compound and a second circumferential portion of a second rubber compound situated adjacent one another. The first rubber compound has a greater stiffness than the second rubber compound so as to provide the tread with greater wear resistance along the first circumferential portion, and the second rubber compound provides the tread with greater traction along the second circumferential portion. The tread may be substantially free of a tread pattern. The second rubber compound may have a greater DIN abrasion value than the first rubber compound. The second rubber compound may have a higher tan delta at 100° C. and/or a higher J″ traction value than the first rubber compound.

A method for forming a composite tread, the method comprising the steps of: forming a coextruded strip of a first compound and a second compound, wherein the first compound is a tread compound, and the second compound is formed from a second compound, wherein the tread is formed from winding the coextruded strip onto the tire building drum while varying the ratio of the first compound to the second compound

A tire comprises a tread portion 2. The tread portion 2 includes a tread ground contacting surface (2s) and at least one main groove 3 recessed from the tread ground contacting surface (2s) and extending continuously in a tire circumferential direction. The main groove 3 has a first groove wall 11. The first groove wall is provided with a recessed portion 15 recessed outwardly in a groove width direction from a groove edge of the main groove 3 on the tread ground contacting surface. The recessed portion 15 is formed of groove wall rubber 8 having a complex elastic modulus larger than that of base rubber 7 forming a main portion of the tread ground contacting surface (2s).

A method for forming a composite tread, the method comprising the steps of: forming a coextruded strip of a first compound and a second compound, wherein the first compound is a tread compound, and the second compound is formed from a second compound, wherein the tread is formed from winding the coextruded strip onto the tire building drum while varying the ratio of the first compound to the second compound

A tread for a tire includes: a first tread zone extending circumferentially, continuously, and entirely around the tire, the first tread zone being formed of a first compound; a second tread zone extending circumferentially, continuously, and entirely around the tire, the second tread zone being formed of a second compound different from the first compound; and a boundary groove axially separating the first tread zone from the second tread zone, the first tread zone, the second tread zone, and the boundary groove entirely forming the tread, the boundary groove having an axial centerline disposed an axial distance from an equatorial plane of the tire. The first tread zone has a first circumferential groove and a sidewall portion defining an intermediate circumferential rib of the first tread zone and a shoulder circumferential rib of the first tread zone.

A tire having a tread comprising at least one circumferential reinforcing element 8 of which at least part of the meridional cross section has the shape of a triangle, the vertex of which is oriented radially towards the outside, the circumferential reinforcing element 8 comprising a skin 81 and a core 82, the skin material being at least twice as stiff as the core material.