PURPOSE: To maintain ground grip properties, by shifting the mutual centers of adjacent blocks in a group of blocks forming in a line in the width direction in the circumferential direction only by 3W25mm, and by bringing the quantity of the variation of grounding area to apparent grounding area within ±0.05.

CONSTITUTION: This tire is provided with a pair of bead portions 4, a trochoid carcass 5 extending over a portion between these bead portions 4, and treads 2, which have outer surfaces spreading along the contours of the carcass 5 extending over both sides from a crown portion of the carcass 5 and consist of a large number of blocks 18-1, 18-2... mutually divided by means of lateral grooves and longitudinal grooves. This tire contains difference-in-level blocks manufactured by shifting the mutual centers of adjacent blocks in a group of a plurality of the blocks 18-1, 18-2... standing in a line in the width direction of the treads 2 in the circumferential direction only by 3W25mm. All blocks are distributed within ±0.05 in the quantity of the variation of the grounding area to the apparent grounding area of the blocks corresponding to the angles of the camber of the tire.