Abstract: A pneumatic tire comprising a tread formed with a plurality of laterally extending groove portions and land portions which are alternatively arranged with a substantially constant pitch in a circumferential direction of the tire, wherein a land portion ratio of a total length of the land portion on a cross line, which is substantially perpendicular to the circumferential direction, to a width of the tread, varies along the cricumferential direction, has not less than two maximum values per the constant pitch and has minimum values, the maximum values each having almost the same values, and the minimum values being not less than 55 percent of the maximum values.

Abstract: A pneumatic bias tire for use on rough road is disclosed, having a carcass with an improved durability. The carcass composed of not less than twelve carcass plies toroidally extending from a tread to sidewalls wherein rubber sheets are interposed between carcass plies of at least the outermost and the innermost bundles each of which comprises at least two carcass plies, the bead side ends and the tread side ends of the rubber sheets being terminated in specific regions, respectively to provide rubber material having an increased thickness between carcass plies so that the rigidity of carcass at the sidewall portion subjected to large compression strain and at the turned-back ends of carcass plies subjected to shearing strain is improved.

Abstract: A pneumatic bias tire for off-road vehicles is disclosed. This tire comprises a bias-structured carcass composed of plural plies each containing organic fiber cords embedded in rubber. In the carcass, the inner plies located near the inner surface of the tire have a rubberized cord arrangement of a more slackened state as compared with the outer plies and further medium plies existent between the inner and outer plies.

Abstract: A highly durable pneumatic tire comprising a bias laid carcass construction formed of superimposed stacked plies is disclosed. The tire comprises a carcass body composed of at least two kinds of ply groups including cords whose diameters are different from one another. The ply groups are arranged such that the cords of outer plies are smaller in diameter than those of inner plies.