A contour Y of a tire outer surface between a tire cross sectional width point P1 and a separating point P3 from a flange includes a protrusive part 10 protruding more than a reference arc RO and a recessed part 11 recessed more than thereof. タイヤ断面幅点P1からフランジとの離間点P3との間のタイヤ外表面の輪郭線Yは、基準円弧R0よりも突出する凸状部10と凹む凹状部11とを含む。 - 特許庁