Pneumatic tire

A pneumatic tire comprising

• a tread portion provided with an asymmetric tread pattern and having an outboard tread edge and an inboard tread edge to be located outside and inside of a vehicle respectively,
• the asymmetric tread pattern comprising:
• circumferential grooves extending continuously in the tire circumferential direction and including an outboard shoulder circumferential groove and an inboard shoulder circumferential groove;
• transverse grooves including outboard shoulder transverse grooves extending from the outboard shoulder circumferential groove to the outboard tread edge, and inboard shoulder transverse grooves extending from the inboard shoulder circumferential groove to the inboard tread edge;
• a row of circumferentially arranged outboard shoulder blocks defined by the outboard shoulder circumferential groove, the outboard tread edge and the outboard shoulder transverse grooves;
• and a row of circumferentially arranged inboard shoulder blocks defined by the inboard shoulder circumferential groove, the inboard tread edge and the inboard shoulder transverse grooves, wherein
• the inboard shoulder blocks have an axial width and the outboard shoulder blocks have an axial width more than the axial width of the inboard shoulder blocks,
• the inboard shoulder blocks and the outboard shoulder blocks are each provided with a plurality of sipes,
• the sipes of each said outboard shoulder block include a circumferential sipe as the axially outermost sipe, the circumferential sipe extending at an angle of not more than 10 degrees with respect to the tire circumferential direction, and
• each said outboard shoulder block has an axially outer sidewall of which surface is provided with a plurality of narrow buttress grooves extending radially inwardly from the outboard tread edge.