| 主权项 |
1. A motorcycle tire suitable for running on rough terrain comprising
a tread portion having a developed tread width and provided with a plurality of blocks protruding from a bottom of the tread portion to define a block tread pattern, wherein the blocks include crown blocks, middle block and shoulder blocks,the crown blocks are disposed in a tread crown region centered on the tire equator and having a developed width of ⅓ of the developed tread width,the shoulder blocks are disposed in a pair of tread shoulder regions extending toward the tire equator from respective tread edges and each having a developed width of ⅙ of the developed tread width, andthe middle blocks are disposed in a pair of tread middle regions between the tread crown region and the shoulder regions, andeach of the blocks has a top face and a sidewall face, the sidewall face extending radially inwardly from the edge of the top face and continued to the bottom of the tread portion,wherein
the crown blocks and the middle blocks are arranged such that at least part of the sidewall face of each of the middle blocks overlaps with the sidewall face of one of the crown blocks in the tire circumferential direction, the top face of each of the crown blocks has an axially long rectangular shape having an circumferential length and an axial width more than the circumferential length, the top face of each of the middle blocks has a substantially pentagonal shape having an axially inner side extending in the tire circumferential direction,a pair of transverse sides extending axially outwardly from the axially inner side and inclined so that the circumferential length of the top face of the middle block is gradually increased, anda pair of axially outer sides extending axially outwardly from the axially outer ends of the transverse sides and inclined so that the circumferential length of the top face of the middle block is gradually decreased,
in a ground contacting patch of the tire in its normally inflated loaded condition in which the tire is mounted on a standard rim, inflated to a standard pressure and loaded with a standard load and the camber angle of the tire is zero,only an axially inner part of the top face of each of the middle blocks contacts with the ground. |
