| 摘要 |
On the surface of a tread portion (1), one central main groove (2) extends in a tire circumferential direction (L) at a pattern center, and a pair of outer main grooves (4a, 4b) extend in the tire circumferential direction (C) each at a position between the central main groove (2) and a respective one of two tread ends (3a, 3b). The central main groove (2) and the outer main grooves (4a, 4b) define central land portions (5a, 5b), and the outer main grooves (4a, 4b) and the tread ends (3a, 3b) define outer land portions (6a, 6b). Among the central land portions (5a, 5b) and the outer land portions (6a, 6b), first circumferential narrow grooves (7a, 7b) are provided only in the central land portions (5a, 5b), extend in the tire circumferential direction (C), have a narrower opening width and a shallower depth than those of the central main groove (2), and have a first groove wall (8) on the side of the outer main groove (4a, 4b) and a second groove wall (9) on the side of the central main groove (2) such that an intersection angle (¸1) between a tread surface (10) and the first groove wall (8) is larger than an intersection angle (¸2) between the tread surface (10) and the second groove wall (9). |
