Originally Posted by
tarsi
I have a 1985 Trek 720 which according to vintage-trek.com came with a 5 speed freewheel. The bike came to me with 6 speeds. Two of the cogs have a fair amount of play between the spacers and adjacent cogs but I'm still waiting for removal tool to see exactly what is going on.
My question is, are there any options to get to a 7 speed setup and if so, what would it involve? The goal is indexed brifter shifting. I've read about using 8 of 9 and 9 of 10 cogs to fit on 7 speed hubs and would be open to any unconventional solutions such as these.
You need to replace the rear hub or rear wheel. Replacing just the hub basically means throwing out everything but the rim and building a wheel with new spokes and hub.
You can go to a 126mm wide 7 speed hub, or cold set the frame to 130 and install a hub that can take anywhere from 7 to 11 speeds. I would be inclined to go to the wider format and a quality 8/9/10 wheel. I like 8 speeds for the low component costs.