Pneumatic tire tread with varying block lengths and varying main groove widths

Abstract

A pneumatic tire which has a tread portion (2) provided with a pair of circumferentially extending main grooves (G) one on each side of the tire equator (C) to define an axially outermost circumferential part (SH) between each main groove and each tread edge (E); each said axially outermost circumferential part (SH) provided with lateral grooves (gs) extending from the adjacent main groove to the adjacent tread edge to be divided into a row of circumferentially spaced shoulder blocks (BS); the shoulder blocks (BS) in each row having at least two different circumferential lengths; the first quotient (Lmax/Lmin) of the maximum (Lmax) of the circumferential lengths divided by the minimum (Lmin) thereof being in the range of 1.25 to 2.00; the width (W) of each main groove changed in the circumferential direction of the tire such that the larger the circumferential length of the shoulder block, the larger the width of a main groove part adjacent to this block; and the second quotient (Wmax/Wmin) of the maximum (Wmax) of the main groove width divided by the minimum (Wmin) thereof being in the range of 1.1 to the first quotient (Lmax/Lmin).

Dependencies are inferred from the claim text.