So I had a chance to go back thru things. Turns out I had all the hub bearings in (thought it possible I might have lost one along the way I took off the new cassette and saw there was a bit of wear and tear where both the 7th gear and freehub engage with each other. Had not seen that before (I think I commented earlier that when I first put on the new cassette all the gears felt a bit sloppy on the freehub).

I then took another look at the old cassette and compared it to the new one and realized the old one wasn't in that bad of shape at all...I would guess at least 1k or more miles left on it (My original reason for the new cassette and chain was because of shifting problems and I thought the cassette was worn out and should be replaced along with the chain). After thinking the new cassette might be ruining the freehub, I cleaned up the old cassette and reinstalled it. I then had what I never had with it...what could be called chain skip even worse than with the new cassette

I still wasn't convinced that somehow the Hyper-C freehub wasn't holding onto 7th gear. I was able to eliminate that idea by marking tops of two adjacent gear peaks (?) on 6th and 7th gear. I figured if 7trh gear slip was the problem, the marks on the 6th and 7th gears would be away from each other after a skip or 2. Tested this a few times and the gear peaks always remained in place. So much for a problem with 7th gear on a Hyper-C freehub.

So, I now know one thing it's not. I don't want to believe it's chain skip (especially with a new cassette), but I can't rule that out yet...at least, not until I can prove otherwise. Although, I used grease as my markers to determine 7th gear slip and while I could tell 6th and 7th gears hadn't slipped relative to each other, I could also see that the grease I put on a 7th gear peak appeared undisturbed (I would expect the chain to have wiped across the top of a gear peak if the chain skipped)....which would tell me the chain wasn't skipping at all (a few assumptions go along with this).

A couple of thoughts and here is where I would appreciate feedback.

Of course, it's hard to specifically determine chain skip when you're riding the bike (at least, not without becoming a hazard to myself 8)...only that something of that nature is going on. If I assume for the moment it is chain skip in 7th gear, is it possible the derailleur may have lost some of its tensioning ability (weakened or broken spring...tho I've looked that)? I would have expected the problem to also show up in 6th and maybe 5th gear. From my inexact testing, the derailleur feels OK. Is this a common problem?

The other thought (and someone mentioned it above) is the possibility I've got a freehub that's at end of life (both the rear derailleur and freehub are original which means they have 18K+ miles on them). I heard some odd noises when I spun the rear wheel right after putting on the new cassette (also made me think I left out a ball bearing). Before putting back on the old cassette, I did a degrease of the freehub and then oiled it up with Tri-Flo. Most of the odd noises went away, but the freehub still feels just a wee bit "hinky" when I turn it (tho I can't make it skip by hand).

So, I'm tempted to buy a new freehub, but I wanted to hear from some folks before I do.

Thanks in advance and cheers....Steph