A motorcycle tyre (1) is described comprising an equatorial plane (X-X) and a tread band (8) comprising a radially inner portion (13) and a radially outer portion (11) respectively comprising a first and a second vulcanized elastomeric material obtained by vulcanizing respective elastomeric materials comprising 100 phr of at least one elastomeric diene polymer, from 30 to 130 phr of at least one reinforcing filler comprising an amount greater than 75% or, respectively, equal to or greater than 80% of a white filler. In the tyre (1) the ratio R1 between the dynamic elastic modulus (E′) and the tandelta measured at a frequency of 10 Hz and at 70° C. of the first vulcanized elastomeric material is comprised between 27 and 35, whereas the ratio R2 between the dynamic elastic modulus (E′) and the tandelta measured at a frequency of 10 Hz and at 70° C. of the second vulcanized elastomeric material is comprised between 15 and 30, the ratio R1/R2 being greater than or equal to 1.1.

A tire includes a tread portion including a first cap rubber layer forming a ground contact surface and having a loss tangent tan δ1, and a second cap rubber layer disposed inwardly in a tire radial direction of the first cap rubber layer and having a loss tangent tan δ2, the loss tangent tan δ2 being greater than the loss tangent tan δ1. The tread portion is provided with a plurality of sipes opening to the ground contact surface, The plurality of sipes, at least partially, extends inwardly in a tire radial direction from the ground contact surface to a. location beyond a boundary between the first cap rubber layer and the second cap rubber layer, and a maximum length L2 of the plurality of sipes in the second cap rubber layer is smaller than a length L1 of the plurality of sipes at the ground contact surface.

A conjugated diene-based rubber including a polymer block (A) containing isoprene monomer unit as the main component and a polymer block (B) containing 1,3-butadiene monomer unit as the main component, wherein at least one of the polymer block (A) and the polymer block (B) contains a unit of a vinyl compound having a functional group interactive with silica, the polymer block (A) has a weight average molecular weight (Mw) in the range of 1,000 to 30,000, and the entire conjugated diene-based rubber has a weight average molecular weight (Mw) in the range of 50,000 to 5,000,000.

A rubber composition of the present invention contains 100 parts by mass of a rubber component (A) containing 45 to 75% by mass of natural rubber and 25 to 55% by mass of a conjugated diene-based polymer, in which a bonded styrene amount of the conjugated diene compound moieties is 25% or less, 1 to 40 parts by mass of a non-modified conjugated diene-based polymer (B) which has a weight average molecular weight of 5,000 or more but less than 40,000 in terms of polystyrene as measured by GPC and in which a bonded styrene amount of the conjugated diene compound moieties is less than 10% and a bonded vinyl amount of the conjugated diene compound moieties is 20% or more, and a filler (C), in which at least one of the conjugated diene-based polymers contained in the rubber component (A) is a modified conjugated diene-based polymer. With the rubber composition, a tire having further enhanced on-ice performance and having both excellent on-ice performance and excellent abrasion resistance is obtained.

There is provided a rubber composition which can provide a tire having an excellent balance of the breaking properties, the rolling resistance performance (low fuel consumption) and the wet grip performance. The rubber composition includes 100 parts by mass of a diene rubber, and 1 to 100 parts by mass of fine particles (A) having a glass transition point of −70° C. to 0° C. and composed of a polymer comprising constituent units of at least one monofunctional monomer. The fine particles (A) have a crosslinked structure crosslinked by at least one polyfunctional monomer having a polysulfide bond in which at least two successive sulfur atoms are bonded together.

A styrenic block copolymer having one or more polymer blocks A and one or more polymer blocks B is disclosed, where “A” is a poly(vinylaromatic) block having a molecular weight of greater than 5 kg/mol. The “B” block has a molecular weight of more than 15 kg/mol, and comprises polymerized 1,3-diene units and vinylaromatic units, wherein the polymerized vinylaromatic units represent 5-40 wt. % of the overall weight of the block “B”. The polymerized 1,3-diene units comprise more than 80 wt. % of polymerized isoprene units in which 45-80 mol % are 1,4-isoprene addition units. The blocks “A” and “B” represent from >5 to <40 wt. %, and >33 to <95 wt. %, respectively, relative to the overall weight of the block copolymer. The polymers have physical properties that make them valuable, e.g., as vibration damping materials.

A tire for a vehicle comprises a tread (2), of which the central part of the tread (2) comprises at least two rubber compounds (221, 222), making up at least 90% of its volume. The first compound (221) is radially on the outside of the second compound (222) and makes up at least 40% and at most 60% of the volume of the central part. The second rubber compound (222) has a Shore hardness DS2 at least equal to 5 plus the Shore hardness DS1 of the first compound (221) and dynamic losses at a temperature of 0° C. and 23° C. that are at least equal to those of the first rubber compound (221). The axially outer parts of the tread are made up of a third compound (223) capable of touching the ground, having a stiffness and a hysteresis that are lower than those of the first compound.

A tire comprises a directional tread of width (W), having a total volume VT, comprising voids (221, 211, 212) defining a voids volume VE. There is defined a volumetric voids ratio TEV=VE/VT, part of the voids (211) delimits blocks (21A, 21B) which are organized into patterns (26) of blocks of pitch P succeeding one another in the circumferential direction (X). Part of the voids forms sipes (211, 212) in one of the patterns. The sipes density SD corresponds to the ratio of a sum of the projected lengths (lpyi) of the sipes in an axial direction to the product of the pitch P of the pattern times the width (W), all multiplied by 1000. SD in any pattern of pitch P is comprised between 10 mm.sup.−1 and 70 mm.sup.−1. TEV is at least equal to 0.29 and at most equal to 0.35.

The present disclosure provides a tire having excellent enduring performance. The present disclosure relates to a tire including a tread containing a rubber composition, the rubber composition satisfying the following relationships 1) to 3) when measured within 180 days after vulcanization: 1) Hso/Hsa×100≥95 wherein Hso: hardness at room temperature, Hsa: hardness at room temperature after heat treatment at 80° C. for 168 hours; 2) As/Ts×100≤70 wherein Ts: sulfur content before acetone extraction, As: sulfur content after acetone extraction; and 3) Swell≤330 wherein Swell: toluene swelling index.

A carcass layer of a pneumatic lire includes carcass cords of organic fiber cords obtained by intertw ining a filament bundle of organic fibers, and includes turn-up portions formed by turning back end portions of the carcass layer at bead portions toward an outer side in a width direction. The carcass cords have an elongation at break (EB) satisfying EB≥15%. An averagetotal gauge (GC)of a center land portion located within a width of 10% of a width of a second widest belt in a belt layer on right and left sides of an equatorial plane in the width direction, an average thickness(SG) of a sound absorptive member inside the pneumatic tire and located within a range identical to that of the center land portion, and the elongation at break (EB) of the carcass cords satisfy 15≤GC/(GC+SG/10)×EB (%)≤25.