| 摘要 |
PROBLEM TO BE SOLVED: To furnish sufficient draining property and steering stability both at the time of a new tire and an abrased tire by making an angle made by a side wall to precedently ground and a land part tread an obtuse angle, gradually increasing the angle from the side of a circumferential auxiliary groove toward the side of a main groove and by making an angle against tire circumference of a crossed line of the side wall and the land part tread in a specified range. SOLUTION: An angleθ1 made by a side wall 10 positioned on the side to precedently ground of the side walls 10, 11 of a center land part 8 facing inclined main grooves 6a, 6c and a land part tread 13 is an obtuse angle, the angleθ1 is gradually increased from the side of a circumferential auxiliary groove 12 toward the side of a circumferential main groove, and an angleα1 of a crossed line L1 of the side wall 10 and the land part tread 13 against tire circumference is within a range of 40-80 deg.. A crossed line of the side wall 10 of a tire in an abrased state and the abrased land part tread makes the angleθ1 against the tire circumference small in comparison with the crossed line L1 of a new tire, and accordingly, it is possible to satisfy both of a draining property and steering stability well in balance by improvement of draining capacity. |
