jbyrkit

I have a circa 1986 cannondale shimano 600 sis bike. i'd like to replace the rear wheel, but i have no idea what modern wheels i could use. This frame has the down tube shifters. The wheel has the freehub (see pic) thing and a 6 speed freewheel. I'm guessing for a new wheel, i need to replace not only the wheel but get a new cassette and derailleur. Any help with possible parts would be wonderful.

revchuck 

A better place to ask this question would be in the Classic & Vintage subforum. They've got the knowledge and are really helpful. You'll need to tell them why you need to replace the wheel (broken? want to upgrade? just because?), and whether you want to upgrade the drivetrain, so they can give a targeted answer.

ThermionicScott 

Shimano and a few other companies still make 6-speed freewheels, and cones for that hub are still available -- there's no reason you couldn't keep your bike running with parts it was designed for.

cpach

If your drivetrain is 6 speed Shimano, your Cannondale has a 126mm frame spacing in the rear. Also, your bike does not have a "freehub thingie", it has a freewheel. You probably can't safely squeeze in a 130mm OLD wheel (which is for modern 8-11 speed). The most modern drivetrain you could run on that frame without hacks is 7 speed, which does bring you into the era of integrated shifters. You'd have to buy used or NOS.

There are also some hacky solutions. You can apparently shove 8 of 9 cogs from a 9sp cassette with a 9 speed drivetrain on there with a 7 speed hyperglide freehub according to Sheldon Brown (or 9 out of 10, or presumably 10 out of 11?) https://sheldonbrown.com/k7.html#up7

What's wrong with the current wheel? You can certainly get new 126mm OLD hubs, but you will probably have difficulty sourcing them with less than 28h, if the modern low spoke count look is what you're after. You definitely cannot just buy new wheels built for modern 130mm frame spacing.

The options I'd consider would be running reasonable used/NOS 7 speed STI stuff, or just run it with as much as the current drivetrain as I could. Possibly with fancy pants old school race wheels.

Beautiful bike, by the way, old Cannondales are neat. Also, this post would have gotten faster and more expert attention in either Classic & Vintage or the mechanics forum.

shelbyfv

There are several threads on old Cannondales in C&V. Folks there have used 130 wheels in the 126 frames with no problems at all. You can run whatever modern drive train you want. I think you can ask a mod to move your post to C&V.