Replacement for Suntour Superbe Tech Rear Derailleur I recently picked up an 85 Cannondale ST500 with a Suntour Superbe Tech rear derailleur. The cage is bent and the bearings in the guides don't feel too fresh. I'm just starting to get into bike maintenance - what's my best option for replacing this? I've noticed I can get something like a Suntour Cyclone for around $30 on ebay - would that work?


Thanks!
You have friction shifters so you don't need to worry about shifter compatibility -- any derailleur can be shifted with a friction shifter provided the shifter pulls enough cable to get through the range of required shifts. So, all you need to worry about is the capacity and extreme cog sizes. 

I'd just buy some Shimano derailleur like a Shimano Acera one for 15-20 bucks.