摘要 |
PURPOSE:To improve the wet and dry performances under high speed running by inclining main lateral groove extending continuously from one end to the other end of tread in circumferential direction while differentiating the inclination angle in central region and from that in the opposite side regions. CONSTITUTION:The tubular tread section striding over a pair of sidewalls is comprised of many main lateral grooves 1 extending continuously from one end 2 to the other end 3 and ribs to be partitioned by said grooves 1. Here, said grooves 1 are inclined with the angle alpha 5-20 deg. against the circumferential direction of tire in central region approximately 1/2 wide of the tread width. Said angle alpha is increased to a range (beta) of 45-80 deg. at one tread side region while to a range (r) of 100-135 deg. at the other tread side region thus to construct the tread asymmetrically. Consequently, the wet and dry performances under high speed running can be improved simultaneously. |