Derailler questions.
 

What are some sign and symptoms of a sick RD? Mine is original and 19 years old -----. What are recommendations for a new 7 spd Rd that can handle one of the Shimano mega freewheels ----- 11-34? thanks in advance. Lp

You can get a Shimano Deore at Nashbar.com right now for like $17. It says "8/9-speed" but will work with 7 just fine. It can handle up to a 34-tooth cog, which is the biggest cog I've ever seen on a mega range freewheel. http://www.nashbar.com/profile.cfm?c...%20Derailleurs

You don't mention if you are having any problems with yours? If not leave it alone.

Loose pivot points, badly worn pulley teeth, and bent or damaged links are typical indications but the most certain sign is poor shifting that can't be traced to cables or shift levers. A 19 year old rd can be a wreck or work like new depending on the miles and care it's had.

I've recently replaced a 15 year old RD - it had been working fine with 7spd until I put on a 9spd shifter, cassette and chain, whereupon shifting became imprecise to the point that it just wouldn't downshift between certain sprockets whatever I did with the cable tension (I even checked the hanger alignment). I noticed that the B pivot had developed a large amount of play and then considered getting a replacement B pivot kit. In the end, noone could tell me whether one of these kits would fit my old RD, so I decided on a new RD. The minute it was fitted and dialled in, shifting became perfect.
The thing I learnt from the episode is that I found it difficult to ascribe the poor function to wear and tear and kept doubting my own ability as a mechanic long past the time when, in retrospect, I should have decided that the old RD was stuffed.

The $17 Deore is the best deal out there. Rivendell loves it.

+1
Can't beat a deal like that.

I did the $17 deore rd with the12-34 mega range freewheel to replace a 6 speed freewheel. Works fine. I am not sure if I would not get the 32 now because the jump on 34 is so large. You will need a new chain if you cannot resist going large-large.
Eric

ps just noticed nashbar has them on sale:
http://www.nashbar.com/profile.cfm?c...Outlet%20Store