| 摘要 |
To improve high-speed durability of the pneumatic tire formed with a directional tread such that transversal grooves are arranged into a herringbone pattern at regular intervals along the tire circumferential direction, the U-shaped cross section of each of the transversal grooves is formed in such a way that a radius (R1) of curvature of a step-out side corner between a side wall and a bottom of each transversal groove which is first brought into contact with the ground along a tire rotating direction is determined smaller than that (R2) of a kick-out side corner therebetween which is afterward brought into contact with the ground at a ratio of about 2 to 5. |
