LeMans was a decent mid-range bike. Unless you paid hundreds of dollars, you did okay. More on Centurions here. In that time era, only the rear derailleurs were indexed. I think this was true pretty much all the way up to the advent of integrated shifter/brake levers. Using friction on the two or three chain rings in the front on road bikes was considered no big deal, especially since the may require regular trimming. Only the rears were indexed.