| 摘要 |
PURPOSE:To enhance wandering resistance, smoothen riding over of ruts, make maneuvering stability excellent, and improve durability. CONSTITUTION:In a shoulder face part 10 of a tire in which two longitudinal main grooves are formed in a tread center face part 9, three fine grooves of each groove width WG 0.9-2.2mm are provided. A groove center line L1 of a first longitudinal fine groove 12 passes an intersection point P1 and an angle alphathereof with respect to a normal N1 of the tread center face part 9 at the intersection point P1 is 10 degrees or less, while groove depth GH1 thereof is 0.8-1.0 of groove depth GH of an outermost longitudinal main groove. A groove center line L2 of a second longitudinal fine groove 13 is nearly parallel to the groove center line L1 and distance X1 thereto in the tire axial direction is 0.04-0.08 of tread ground contact width W, while groove depth GH2 thereof is 0.6-0.8 of the groove depth GH1. In a third longitudinal fine groove 14, groove depth is 0.1-0.3 of the groove depth GH1, and distance X2 of the centerline to the centerline L1 in the tire axial direction is 0.1-0.2 of the tread ground contact width W. |
