Over a year ago I started on a fix-up of my 34 year old Rex Criterium and, with a lot of help from this forum and eBay, I took it out for it's first ride today (pictures tomorrow, I promise).

I thought I would go to the local rails to trails bike path near Gainesville Fl and ride a mile or so in each direction so I could set-up the shifters, brakes ,seatpost, stem height etc but it was such a beautiful day and the bike felt so very good right from the start that I rode the path front to back and then the return trip for a total of 32 miles.
Only issues I had (besides under inflated tires...too nice of a day to stop) was the chain jumps under pressure on two of the rear sprokets, the first and the third. The rear cluster is over 30 years old and has had a lot of miles on it so I guess it is some sort of wear but I can't see it...the chain is brand new.
What is this I read about cluster teeth being "twisted" to improve shifting..also the cluster seems to wobble a bit when I look down while coasting, is this a concern? Should I change the whole thing or just the offending sprockets?

BTW, if you are ever in North Florida this is a wonderful bike path...goes from Hawthorne to Gainesville.

Mike