Terrierman

I had trouble with my rear derailer for the last couple of months. Not serious, but aggravating. I could adjust it to shift right going up, or going down, but I could not for the life of me get it to work right going both ways. And it seemed to be slow if that is a word that works. I was in town today and took it to the LBS where I bought it and asked their wrench guy to please take a look at it. He put it on the rack and checked chain alignment which was fine. Put the derailer back on and started adjusting cable tension and Praise The Lord it would not work right for him either. Luibed the derailer and that seemed to help a bit but things were still not really right. It did not take him long to zero in on some crud and corrosion inside the cable housing or guide or whatever the right term is. I've occasionally ridden the bike in some pretty crap weather over the winter, and it looked like grit with some salt corrosion? Cleaned that off, lubed it up and things were better. I now own a container of tri-flow and the knowledge of how to clean and lube cables. Who knew? (not me, I'm a total rookie). Anyway, it seemed worthwhile to pass on.

Louis

Glad it was something simple, funny how a little crud in the right (wrong?) place can cause so much trouble.

Some LBS would have tried to sell you a whole new drivetrain if the horror stories I've read on the internet are true. Buy that guy a pizza.

europa

Muck is funny stuff. You can have a perfectly operating system covered in congealed gunk and rust ... and a surgically clean non-operating system thanks to a bit of grit in the wrong place. Glad is was an easy fix. I like cheap fixes.

Richard

Velo Dog

That's been the trouble whenever Ive had a non-obvious shifting problem. Another frequent cause of poor rear shifting is friction where the cable runs under the bottom bracket. It's exposed to all kinds of gunk, and oiling it seems like a bad idea because dirt will stick to the lube, but I've cured a lot of shifting just by brushing that off and maybe dripping a little dry lube on it.
Pulling the cables out of the housing and greasing them used to be a normal maintenance chore, but now that everybody uses lined housing, it's often overlooked. Works for brakes, too.

maddmaxx 

I have become a fan of Avid's Flak Jacket Cables.
I always thought the sealed cable runs were for top tube cables only but the most receint package I opened had 2 small black tubes in it about 6 inches long.
I tested them and they fit through the holes in the bottom bracket guide.
Now I have the down tube cables covered up for their whole length.
Where the tube comes up to my front derailleur I use a small piece of sponge to wipe the crud off the inner wire before it gets inside.

stapfam

Definitely a bag of doughnuts at least.

You have found an LBS that is worth nurturing so keep in with them.

Terrierman

Here's what makes it even better. The total charge for service was the purchase price of the little bottle of Tri-Flow. They are a good bike shop, they're even friendly!

leob1

Any time I work on a bike with sticky shifting or braking, like if the calipers are slow to release, I will clean and lube the cables and housings, any rust on the cable, the cable and housing get replaced. That usually gets rid of most problems.
Now you know for the next time.