| 摘要 |
PURPOSE:To improve all of the dry performance, wet performance and high speed durability of a tire by forming a circumferential sub-groove extending zigzag in the circumference direction between a pair of circumferential main grooves near by the equator line. CONSTITUTION:A tread section T is formed with two pairs of main grooves 2a, 2b, 3a and 3b symmetric in relation to the equator line and parallel to each other in the circumferential direction. A plurality of notch grooves 4a and 4b are formed in equally spaced relation extending from the grove wall on the side of the equator line 1 between a pair of circumferential main grooves 2a and 2b near by the equator line 1 toward the equator line 1. In this case, a circumferential sub-groove 15 is formed extending zigzag without crossing each of the notch grooves 4a and 4b and crossing the equator line 1. The width of the circumferential sub-groove 15 is set nanowen than the width of the circum ferential main grooves 2a through 3b. This divides the land section divided by each of the circumferential main grooves 2a and 2b into a pair of ribs 16 and 17. |
