| 摘要 |
<p>A pneumatic tyre comprises a circumferential groove (10) disposed in the axial centre (Yc) of the tread portion (2), circumferentially spaced main grooves (11) disposed on both sides of the tyre equator, the main grooves (11) extending axially outwardly beyond the tread edges (Te), while inclining to one circumferential direction and increasing the inclination angle ( alpha ) of the groove centre line (N1) with respect to the circumferential direction (C(No)), auxiliary grooves (12) each disposed between the circumferentially adjacent main grooves (11) and extending from a middle portion (Yn) of one of the main grooves towards the above-mentioned circumferential direction beyond the tread edge (Te), each of the auxiliary grooves having a part (12A) equidistant from the adjacent main grooves (11) and having a length more than 30 % of the length (K) of the auxiliary groove (12). The intersecting angle ( beta ) of the auxiliary grooves with the main grooves (11) is in the range of from 20 to 60 degrees. <IMAGE></p> |
