direction of the tire or perpendicular to a circumferential direction of the tire it is preferable to provide the cuts 5 spaced apart a substantially equal distance in the circumferential direction or with a constant interval lengths l of the cuts are progressively reduced as they approach from extending corners 3 to retracting corners 4 of the ribs the progressive reduction in length l of the cuts does not decrease the rigidity of the retracting corners 4 of the ribs 2 more than that is required for this purpose but sufficiently decreases the rigidity of the corners 3 without any conspicuous discontinuity of the rigidity of the ribs between the corners 3 and 4 whereby the railway wear can be effectively mitigated to a required and sufficient extent without sacrificing wear resistant characteristics such as life associated with the wear of the tire and the like the length l of the cuts 5 at the extending corners of the ribs is the maximum l 39 which should be within 30 80 of the amplitude l of the zigzag of the circumferential grooves 1 in order to more effectively mitigate the railway wear moreover it is preferable that the pitches p 39 or spaced distances of the cuts 5 in the.