Patent ID: 8181682

Claim:
A pneumatic tire provided with main grooves extending in the tire circumferential direction and transverse grooves connected to the main groove formed on a tread, and with blocks formed by the main grooves and the transverse grooves, wherein the phase difference of the two transverse grooves connected to the main groove is within 25% of the circumferential length of the blocks, and projected portions are alternately provided in both sidewalls of the main groove, the circumferential length of the projected portions is 20% to 45% of the circumferential length of the blocks, in the cross-section of the width direction of the main groove the edge of the projected portions at the groove bottom is 2% to 25% of the width of the main groove from the centerline of the main groove, and the outline of the projected portions is at least on a virtual surface that connects the edge of the main groove at the tread surface and the edge of the projected portions at the groove bottom, and the pneumatic tire is provided with one or a plurality of sub-projected portions further projected away from the virtual surface, toward an imaginary plane extending perpendicular to the main groove bottom and through the center line thereof, the maximum width portion of each of the sub-projected portions being within the range of 30% to 80% of the depth of the main groove, and the width of the maximum width portion being at least not less than 1.0 mm.