| 摘要 |
PURPOSE:To enable both a stone-bite preventing effect and a drain effect to be improved by overhanging a rack step along a side wall in a tread groove while tilting a wall surface in a bottom side of the rack step in a direction spreading a width of the tread groove. CONSTITUTION:A tire has a tread groove 1 extending along the peripheral direction of a tread part. Here the tread groove 1 provides in its side wall 2 a rack step 3 overhanging from the side wall 2 protruding to the tread groove 1. While a rack step side wall surface 4 in a bottom side from the rack step 3 is opposed facing diagonally in the bottom part direction of the tread groove 1, further tilting in a predetermined angle theta with respect to a perpendicular I-I drawn in a tread surface 5 while tilting in a direction spreading a width of the tread groove 1 in the bottom from an upper surface 6 of the rack step 3. In this way, even when the large rack step 3, having a sufficient stone-bite preventing effect, is provided, preventing a drain effect of the tread groove 1 from deteriorating, traction performance on a wet road surface can be high held. |
