| 摘要 |
PURPOSE: To effectively improve respective performances for wet/drainage, low noise, and control stability, without sacrificing the other performances. CONSTITUTION: This pneumatic racial tire is provided with at least a pair of main grooves in the circumferential direction extending in the circumferential direction of a tread on a pattern center zone, and a plurality of slant main grooves 4 extending from a pair of the main grooves 1 to the pattern end sides, slanting in the same directions against the main grooves 1, and opening at the tread grounding ends TE. The each slant main groove 4 is constituted of a steep slant part 5 positioned in the vicinity of the pattern center and a gentle slant part 6 positioned in the vicinity of the tread grounding end TE. The angleθ1 of the steep slant part 5 against the circumferential direction or the tread is set 0-30 deg., the similar angleθ2 of the gentle slant part 6 is set 70-90 deg., and the surface height of the tapering end part on the pattern center side of a land part 7 defined by the main groove 1 in the circumferential direction and the slant main groove 4 is smoothly lowered toward the extreme end side. |
