| 主权项 |
1. A pneumatic tire for a motorcycle, having a pair of bead portions, a pair of sidewall portions continuous with the bead portions, a tread provided to extend in a toroidal shape across the pair of sidewall portions, and a directional pattern provided at the tread specifying a rotation direction when the tire is mounted on a vehicle; comprising:
a main groove in a bent shape, constituted of a first groove extending in a tread circumferential direction within a ground contact region in straight running, of a ground contact surface of the tread, and a second groove extending from an end portion, on the side of the rotation direction specified by the directional pattern, of the first groove toward the outer side in a tread width direction with slantly approaching the specified rotation direction; and an auxiliary groove formed at a position on the outer side in the tread width direction of the second groove and distanced in the tread circumferential direction from an end portion, on the side of the rotation direction specified by the directional pattern, of the second groove such that the auxiliary groove extends toward the outer side in the tread width direction with slantly approaching the specified rotation direction, wherein, provided that a groove width of the main groove at a connection portion of the first groove and the second groove is A (mm), a groove width of the second groove at an end on the outer side in the tread width direction is B (mm), and a groove width of the auxiliary groove is C (mm), A >B≧C, wherein, provided that a distance in the tread width direction between the tire equatorial plane and a bending point on the outer side in the tread width direction of two bending points connecting the first groove and the second groove in the bent shape is d (mm); and a tread width is TW (mm), 0.25≦d/TW ≦0.45. |
