Shifter conversion
 

I have an old Shogun (no idea what model, all tags, decals, etc have been removed) with 2x7 gearing. I want to convert the downtube shifters to STI levers but don't know if my components are compatible. I have all shimano 600 components and want to put shimano tourney A070 shifters on. Will my derailleurs work without having to be replaced?

Help a newbie out.....I have no idea how to use a forum.

Should work fine, as long as the 600 rear derailer is SIS compatible, meaning a 6208 or later:
VeloBase.com - Component Listing

It's the RD-6400. So it should be good?

yes, throwing on the tourney will work just fine.

there are Shimano 600 6400 brifters. if it were me, id go to ebay and try to find a used pair. You'll probably be paying around the same, and they're higher quality and the same groupset.