| 摘要 |
<p>Provided is a tire and a race competition method whereby it is possible to reduce the fund for participating in a race competition by maintaining a lowered grip force and suppressing variation in grip force even if the degree of abrasion is increased, thereby reducing the frequency in exchange of a tire. Since a grip control tread (3b) is provided with grooves (7), the area of a second grip surface (6) is reduced by adjusting the number or the width (the dimensional value in the right and left direction in fig. 2(c)) of the grooves (7), so that the pressure applied onto the second grip surface (6) can be increased. Consequently, respective areas of the first grip surface (5) and second grip surface (6) grounding onto the road surface (R) can be maintained equally to that of a unused (new) tire (1) by adjusting the degree of abrasion of the grip control tread (3b) equally to that of a grip tread (3a), and therefore, the grip force of the tire (1) can be prevented from lowering during use of the tire.</p> |
