Patent ID: 8336593

Claim:
A pneumatic tire having a carcass ply, belt plies being disposed radially outwardly of the carcass ply in a tread portion, a belt-reinforcing structure being provided radially outwardly of the belt plies, the belt-reinforcing structure having organic fiber cords spirally wound in a circumferential direction of the tire, the belt-reinforcing structure comprising a center reinforcement layer and end reinforcement layers, the center reinforcement layer being disposed radially outwardly of a center region of the belt plies, the end reinforcement layers being disposed radially outwardly of end regions of the belt plies located on opposite sides of the center region in an axial direction of the tire, the center reinforcement layer having an organic fiber cord formed of organic fiber having an elastic modulus of 10000 MPa or less, each end reinforcement layer having an organic fiber cord formed of a hybrid cord, the hybrid cord having a filament of organic fiber with an elastic modulus of 10000 MPa or less and a filament of organic fiber having an elastic modulus higher than that of the organic fiber with an elastic modulus of 10000 MPa or less, the filaments being twisted together, wherein the end reinforcement layer has a two-layer structure in which the hybrid cord is spirally wound from an axially inner side of the tire toward an axially outer side of the tire, is turned in an opposite direction at an edge of the belt-reinforcing structure and is spirally wound from the axially outer side of the tire toward the axially inner side of the tire, and in which opposite edges of the hybrid cord are away inwardly in the axial direction of the tire from the edge of the belt-reinforcing structure, and wherein the end reinforcement layer has a first end reinforcement layer part adjacent to the belt plies and a second end reinforcement layer part disposed radially outwardly of the first end reinforcement layer part, wherein the first end reinforcement layer part is substantially as equal in width as the second end reinforcement layer part, and wherein an end reinforcement layer placed radially outwardly of at least one end region of the belt plies is configured such that the second end reinforcement layer part is disposed so as to be partially offset with respect to the first end reinforcement layer part in the axial direction of the tire.