| 摘要 |
PURPOSE:To reduce stone-picking without lowering a wet lip performance, by forming at a tread vertical grooves located predeterminedly against an equatorial surface, and also, forming repeatedly changing portions where groove widths change circumferentially. CONSTITUTION:Vertical grooves G1-G3 are formed at a tread portion T. At this time, the center of the vertical groove G1 is made to be located on an equatorial surface Co, and distances h2, h3 between the groove centers of vertical grooves G2, G3 and the equatorial surface Co, are both set less than 2/3 times distance H between the equatorial surface Co and a tread end edge E. Also, changing portions 6 where groove widths W change in th perimeter direction of a tire, are formed repeatedly at a pitch P. These changing portions 6 are so formed that respective groove walls are formed of meeting-at-right- angles portions and inclination portions, and the meeting-at-right-angles portions and inclination portions of respective walls are arranged so as to face each other respectively. As a result, stone picking can be reduced without lowering a wet lip performance. |
