Sumitomo Rubber Industries Limited

The Goodyear & Tire Rubber Company

David Robert Watkins

Michael Jackson

Nigel G Nock

Michael R Corner

Paul Stephens

Malcolm Jeremy Board

Arthur R Williams

Gary Terence Barrett

Gerald A Griffiths

John Christopher Valentine

Tire

A motor-cycle tire () comprising a ground contacting tread () reinforced between its edges () by a breaker assembly and having in its normally inflated fitted condition a camber value C/L of between 0.5 and 0.7, a reinforcing carcass ply () extending radially inside the breaker assembly and between two bead regions () and wrapped in each bead region around an annular bead core () from the axial inside to the outside to form carcass ply turn-ups () and between the tread edges () and bead regions (), tire sidewalls () wherein the breaker assembly comprises two breaker plies () comprising reinforcing cords oppositely inclined with respect to the circumferential direction of the tire characterized in that the tread comprises two different rubber compounds, the first rubber compound extending in a continuous first layer between the tread edges () and the second rubber compound being disposed in a second layer radially outwardly of the layer of the first rubber compound to form the tread running surface in the central portion of the tread.

Motorcycle tire having tread including two different rubber compounds

An improved single-stage method for building a tire includes the steps of forming a cylindrical-shaped carcass with axially extending carcass reinforcing cords, fitting annular bead hoops onto the radially outer surface of the carcass ply at positions axially inward of each of the carcass ply edges, assembling a plurality of breaker plies, including one wide breaker ply, centrally onto and about the radially outer surface of the carcass ply, and fitting onto this cylindrical assembly the remaining components of the tire to form a cylindrical green tire assembly, wherein the radial bias angle of the carcass reinforcing cords in the vulcanized tire changes progressively from 90&deg; in the regions of the bead hoops to as low as 70&deg; in the central crown region.

Single-stage method of fabricating radial tire with breaker ply extending between bead regions

A tire for a vehicle having at least one wheel at each corner, the tire comprising a non-longitudinal ground contacting tread extending axially between first and second axial edge regions and having tread grooves formed therein, wherein in the first axial edge region of the tread, the tread grooves are oriented substantially in the tire circumferential direction and in the second axial edge region of the tread the grooves are oriented substantially in the tire axial direction and in a third axial region of the tread axially between the first and second edge regions the orientation of the grooves changes progressively from circumferential to axial.

Tire having tread including orientation of grooves changing across entire tread width

A pneumatic radial tire having in axial cross-section a highly curved tread is reinforced by a breaker assembly with improved resistance to breaker edge looseness. The breaker assembly includes one breaker ply which extends between two bead regions and has its edges disposed between a carcass main portion and a carcass turn-up portion. An improved single-stage method may be employed for building the tire.

Tire with breaker ply extending between bead regions

A tire for a two-wheeled vehicle comprising a ground contacting tread having at least one tread groove formed therein and extending axially from the tread center to the tread edge, wherein in a first region of the tire tread, which is the central tread region and is the region of contact between the tire and the ground when the motorcycle is in the condition of moving in a straight line, the alignment of the tread groove is substantially circumferential, and in a second region of the tire tread, which is at the axial edge of the tread and is the region of contact when the motorcycle is in the condition of turning under maximum cornering, the alignment of the tread grooves is substantially transverse, and in a third region, which is the tread region between the first central region and the second axial region and which is the ground contacting region when the motorcycle is turning at less than the maximum cornering condition, the groove alignment changes progressively axially outwardly from substantially circumferential to substantially transverse so that in the first, second and third axial regions of the tire tread the tread grooves are substantially aligned with the resultant forces acting on the tire tread surface in the contact region between the tread and with the ground.

Method of determining groove angle to give optimum tread wear

A tire for a vehicle having at least one wheel at each corner, the tire comprising a ground contacting tread extending axially between first and second edge regions and having tread grooves formed therein, wherein in the first axial edge region of the tread the tread grooves are aligned substantially in the tire circumferential direction and in the second axial edge region of the tread the grooves are aligned substantially in the tire axial direction and in a third axial region of the tread axially between the first and second edge regions the alignment of the grooves changes progressively from circumferential to axial.

Method of manufacturing tire including grooves

Vehicle tire

A radial motorcycle tire having improved lateral grip under camber with good stability, wherein the tread is reinforced by two main breaker plies comprising parallel reinforcing cords oppositely inclined with respect to the tire circumferential direction and a supplementary breaker ply is disposed radially outward of the main breaker plies and comprises a cord reinforced central ply portion and lateral outer side ply portions disposed on opposite sides of the central ply portion, said lateral side portions comprising rubber having no cord reinforcement.

Motor-cycle radial tire

A motorcycle tire having in its normally inflated condition a camber value C/L of between 0.5 and 0.7 and having a maximum axial width between edges of a ground contacting tread wherein in axial cross-section the tread comprises two tread rubber components of different rubber compounds joined by a scarf joint, the scarf joint having a width less than the width of the tread and having an intertread ply comprising reinforcing cords interposed between the two tread rubber components.

Motorcycle tire

A motorcycle tire comprises a tread reinforced between its edges by a breaker assembly and having in its normally inflated fitted condition a camber value C/L of between 0.5 to 0.7, a reinforcing carcass ply of rubber covered cords radially inside the breaker assembly and extending between two bead regions and wrapped in each bead region around an annular bead core to form carcass ply turn-ups, and tire sidewalls between the tread edges and bead regions, wherein under the tread is disposed radially inward of the breaker assembly a secondary carcass ply of rubber covered cords and between the carcass ply and the secondary carcass ply is disposed a rubber member extending from tread edge to tread edge.

Motorcycle radial tire with rubber member between carcass plies

A motorcycle radial tire comprises a tread reinforced between its edges by a breaker assembly and having in its normally inflated fitted condition a camber value C/L of between 0.5 and 0.7, a reinforcing carcass of radially disposed cords extending radially inside the breaker assembly and between two bead regions and wrapped in each bead region around an annular bead core from the axial inside to the outside to form carcass ply turn-ups, and tire sidewalls between the tread edges and bead regions, the tire characterized in that the breaker assembly comprises two breaker plies each reinforced with aromatic polyamide cords oppositely inclined with respect to the circumferential direction of the tire and a supplementary ply disposed radially adjacent to the breaker plies and reinforced with nylon reinforcements laid parallel to each other and disposed at an angle in the range of 75.degree.-90.degree. to the circumferential direction of the tire.

Motorcycle radial tire with supplementary breaker fly

Motorcycle radial tire with supplementary breaker ply

A radial tire for a four wheeled vehicle comprising a reinforced carcass ply extending between two bead regions through sidewall regions to a tread region and a reinforcing breaker disposed in the tread region extending circumferentially around the tire radially outside the carcass ply wherein the tread region is substantially curved in cross-section and has a camber value C/L of between 0.25 to 0.75. The breaker includes at least two plies of reinforcing fabric, a narrower breaker ply which is radially innermost and a wider breaker ply which is radially outermost, and each of the breaker plies except the outermost ply has adjacent to each of its lateral edges a circumferentially extending support strip which extends laterally outward from the edge of the breaker ply to at least the lateral position of the edge of the widest breaker ply.

Growing community of inventors

Sutton Coldfield, United Kingdom

David Robert Watkins