Originally Posted by
Bigbus
The Front setup is 52/36T and the rear cassette (free hub) all the gears fall apart when you remove it. Does that help? From the research I've done on the bike it seems that most of them came with a 5 spd rear for a total of 10 speeds and only the later 80's stepped up to the 12 spd which I have. With my current setup I cruise between 19 and 21 MPH (52/14) so whatever that makes my cadence. I just feel like I got more power left in my legs-- but not more speed.
What holds the cassette to the freehub? Does the smallest cog screw on?
With a 36 teeth inner chainring I think you might have a lot of trouble getting a front derailleur to shift from that to a 56 teeth chainring. That's 20 teeth. The problem I see possible happening is the cage of the derailleur catching and jamming the chain before the shift is completed.
Can you post an image of your cassette on the wheel but off the bike? Also an image of your front derailleur might help.
I still think that your best bet would be to get a rear wheel that uses a Hyperglide cassette. You might be able to get a good used one at a bicycle co-op if there's one near you or perhaps used wheel at a bicycle shop.
Cheers