Rear deraileurs - get what you pay for?

Schobiedoo

I've got a shimano LX rear deraileur on my bike, I've been having some problems getting the gears working as I want them. I've got them so that they shift precisely as the cable is pulled (i.e. going to larger rings) so that each click moves the chain 1 ring but on the way back down I can't seem to make them shift one ring at a time, sometimes they don't shift and other times they jump 2-3 rings.

So question
1. Do you get what you pay for and to get a smooth single ring shift on the way back every time you need a more expensive deraileur.
2. Is it likely that I've set them up incorrectly
3. Is it likely that the cable run is full of gunk making the return not smooth

Any thoughts?

supersonic

1: not really, though they do last longer and weigjh less

2: yep!

3: most likely!

Check the hanger is straight too.

nicklouse

sounds like a dirty cable or poor routing.

woodywmb

More than likely dirt in the last section of cable going into the rear mech. To test it, pull on the bare inner as it runs down the seat stay. Your mech should carry the chain across the rear sprockets either one way or another (depending on whether it is low or high normal). If the wire doesn't immediately return to its taut position after you tug on it then you need to shoot degreaser and WD40 through the outers. Or replace the cable. The rear derailleur you have is a fine piece of kit and any upgrades would only result in marginal improvements.

camerauk

Had this on my bike a few months back changed the inner cable for a teflon coated one and that sorted it on close inspection of the old cable there was a very very small fray in the cable

.blitz

Schobiedoo wrote:

1. Do you get what you pay for and to get a smooth single ring shift on the way back every time you need a more expensive deraileur.

No. New Deore is way better than knackered XT.

Schobiedoo wrote:

2. Is it likely that I've set them up incorrectly

Yes.

Schobiedoo wrote:

3. Is it likely that the cable run is full of gunk making the return not smooth

Yes.

HTH

Kiblams

In my recent experience fine tuning a cheap Tourney derailleur working on a 9speed cassette, it is all in the set-up. If I can get a 7speed derailleur working like a charm then you definatly shouldn't need to buy a new one!

Give it some TLC and save some money (always good in recession)

Schobiedoo

Thanks for the responses, I'd better set aside some time to do some cleaning and tweaking then before the weekend!

bomberesque

replacing the cable and outer is probably the best upgrade you can make to a 1 or 2 year old bike IMO. cleaning and lubing is one thing, but new cable and outer is the way to go considering the very small cost.

I choose to run full length outers for teh rear deurallier and my experience is that this gives better shifting and longer cable life even using bog standard materials (not special hoofy doofy teflon coated stuffs, nice as they are)