Originally Posted by Grim

Welcome to the C&V forum. I recently found a Grandprix in the trash and dragged it home. The frame is really not that heavy considering the vintage. The lug works is really interesting. As somebody else mentioned "try to find a set of quality alloy wheels" and it will take quite a bit of weight off the bike.

I have been trying to get and exact date on mine and it seems to be equipped almost identical to yours. My best guess is a 73. The Simplex prestige Derailleur seemed to fade after that. It was the first year that I could match the paint color and parts mine has.

I was going to try to do a correct restore on mine but that Simplex is a problem. They just don't last and mine is bent up quite badly. For the short term I think I will convert mine to a single speed.

The cranks may be a problem. cottered cranks are notorious for being sloppy. The threading is not common to anything new. Swapping out the Cottered shaft to a square shaft is the easiest thing to do as you can still retain the original bearing cups. This is detailed in the links posted above for Sheldon's (RIP) web site.

Yard sales and thrift stores would be a good place to find a parts bike. just make sure you don't get into that hole a lot of us seem to dig...the parts bikes end up being projects and it never ends.