These bikes are really hard to find info about. By the ders being Eagle & Thunderbird Shimano parts and looking original to the bike, it would seem maybe that this is a 1974-76 bike? Or maybe the model numer of "770" means it was a '77? I dunno, you google search this company and you get like 3 results that include anything about "bike". And all 3 SuperBikes I found were yellow 3 speed cruisers.

I dunno, seems like this one might be fun as a fixie. It is a bit tall for me though. I can stand over the TT with both feet on the ground but there is no clearance zone space.