Rob May could have retired from the Duluth music scene on the laurels of “Mohawks,” the local punk classic written during time with the band Giljunko, but there was still more rawking to do. The shirts have less vomit on them these days, but the raw and the rowdy music continues to spew forth with irreverence and mirth. Sometimes May performs solo; other times old pals from Duluth bands of yore come calling. Sometimes there are mohawks, mohawks, mohawks, mohawks. Sometimes there aren’t.