I don't think it is a Roubaix, but it looks like a mid 1980s Fuji. Probably mid level, since there is a derailleur hanger. Also, it has fender eyelets, cable guides, and nutted brakes. It may not have any original components left, so I am concentrating on the frame details. The 1984 Club Fuji looks pretty similar: http://www.classicfuji.com/ClubFuji_1984_Page.htm