Patent ID: 8511358

Claim:
A pneumatic tire having three circumferential main grooves disposed asymmetrically with respect to a tire equator, said pneumatic tire having a tread surface divided by the tire equator to an outer region, meaning at the vehicle outer side when the tire is mounted on the vehicle, and an inner region, meaning at the vehicle inner side when the tire is mounted on the vehicle, and having one single outer region circumferential main groove disposed in said outer region and extending in a circumferential direction of the tire, and first and second inner region circumferential main grooves disposed in said inner region, said first inner region circumferential main groove extending in the circumferential direction on a tire equator side and said second inner region circumferential main groove extending in the circumferential direction on a ground contact edge side, wherein: a central region between said outer region circumferential main groove and said first inner region circumferential main groove is formed into a rib extending continuously in the circumferential direction, an outer shoulder region between said outer region circumferential main groove and an outer region ground contact edge is provided with outer inclined main grooves each extending at a slant with respect to the circumferential direction and crossing said outer shoulder region, thereby forming said outer shoulder region as a row of outer blocks disposed at intervals in the circumferential direction, each of said outer blocks is provided with an inclined sub-groove having an inclination direction different from that of said outer inclined main grooves with respect to the circumferential direction and extending between adjacent said outer inclined main grooves, thereby dividing each of said outer blocks into a first block portion on a tire equator side and a second block portion on a ground contact edge side, said outer region circumferential main groove, said first inner region circumferential main groove and said second inner region circumferential main groove are provided, at only an inner intersection part at which the tread surface intersects with an inner groove wall surface, meaning at the vehicle inner side, of each of the circumferential main grooves, with a chamfered edge-like cutout portion, and said inclined sub-groove is provided, at only an outer intersection part where its outer groove wall surface, meaning at the vehicle outer side, intersects with the tread surface, with a chamfered edge-like cutout portion.