Well I finally got all of the parts I needed last week. So yesterday, after nursing my birthday hangover, I proceeded to make the conversion.

It had a 6-speed Uniglide freehub/cassette set-up that was 13t-23t (not so good for touring). I wanted to convert to lower gears but most of the cogs were pretty worn and NOS UG cogs are getting scarce and pricey. So I figured switching to Hyperglide would make it easier to replace cogs in the future and make for smoother shifting. I also wanted to stay with 6-speed so I could still use the stock Shimano index shifter.

SO, after much research I found a 6-speed cassette (13t-28t) from Nashbar, I got a Shimano STX-RC, 7-Speed Freehub Body and a SRAM PC-58 Chain from bikeman.com and. I also got an stx-rc drive-side cone and a few different spacers just incase (but I didn’t need them).

I disassembled the old hub completely for cleaning and repacking before installing the new freehub body. I played around with the new freehub and cones I had on hand. It turns out that I could use the original cone but it falls below the freehub body opening so the drive side cone and nut have to be installed and tightened before inserting the axle. Future removal of the axle will have to be done from the left side. I could’ve used the new cone if I upgraded to a longer axle and re-spaced the rear fork.

After rebuilding the hub I had to figure out how to get the cassette in place. I ended up putting one extra 6-speed spacer behind the cassette to move it out a little since the new freehub is a little wider than the original. I suppose I could’ve put it on the outside but I felt the lockring would work better against a metal cog than a plastic spacer.

I shortened the new chain to match the length of the old chain and installed that. I didn’t use the Powerlink. I figure if I need to add a link for the bigger cogs I will add the Powerlink later. After a quick derailer adjustment it was working great. SO SMOOTH!

I will take the bike out for a spin today after work to see if everything will hold up under load… but it seems to be a smooth conversion.

Shimano said it couldn’t be done. Most of the people at the local shops and on the phone had no idea what I was talking about. I found most of the info I needed either here or on sheldonbrown.com.

Thanks all,
David