10 speed 105 woes

collywobble

Hello Everyone,

My bike is about 5 years old and came with 105 10 speed. I have had loads of problems with this and have upgraded most parts to Ultegra. This is in contrast to my other bike which runs old 9 speed 105 and never misses a beat.

I have just fitted a new cassette, cables and the chain is fairly new. The bike has just come out of the workshop (again) and after about two miles the chain is jumping around all over the place. This is particularly bad on the middle cogs of the cluster. I also have problems with the front mech not engaging properly, it always seems to take two sweeps to get it right.

I live in a hilly area and this is spoiling my riding. I have tried fiddling with the limit screws on the rearderailleur and on the front mech it makes a difference, but after a couple of miles, it all seems to fall out of adjustment. The bike is clean and well maintained.

Any help is appreciated and thanks

majormantra

Mech hanger bent? Good quality outers of the right type? No kinks in the inner? How new is "fairly new"? Have you checked for chain stretch?

Do the levers release cable cleanly? If they're gummy you can try freeing them up with a blast of GT85.

The limit screws set the limits and nothing else. Leave them alone once they're set. Cable tension affects movement up and down the cassette.

chrisvanderkaap

MajorMantra wrote:

Mech hanger bent? Good quality outers of the right type? No kinks in the inner? How new is "fairly new"? Have you checked for chain stretch?

Do the levers release cable cleanly? If they're gummy you can try freeing them up with a blast of GT85.

The limit screws set the limits and nothing else. Leave them alone once they're set. Cable tension affects movement up and down the cassette.

+1

garethjohn

Read this:
http://sheldonbrown.com/derailer-adjustment.html#chain

garethjohn

Its usually just a tension thing which can be fine tuned with the adjusting barrel on the rear mech. Just spin the pedals ideally on a bike stand and wind the barrel up or down to suit. When turning the barrel through a few revs you should start to hear the chain rattling and will eventually change up or down a gear. Skip up and down through the cassette by changing gear to check every gear engages cleanly, if not fine tune until ok.

smoggysteve

I would check to see if the correct spacer shim was fitted, if at all. A missing spacer making the cassette out of line would be more acute in the middle cogs.

collywobble

Thanks for all the replies and useful information. I will check it again tomorrow.

Chris87

Has it come out of your workshop or a professional one?

If your doing the work yourself it might be worth taking it to your LBS and asking them to show you what you have done wrong so you will know for the future.

Lazybike

Does it skip on both chainrings?.....If it only skips on one then you have a worn chainring, I'm guessing if you live somewhere hilly it'll be the small thats worn.

markos1963

My money would be on a bent hanger

duckson

Is your front derailleur "just" above the outer chainring or miles above it?
The clearance between the top of the outer chainring and the bottom of the derailleur cage should be about the width of a 2p coin.

ratsbeyfus

Could also be a bent derailleur rather than hanger. Happened to me, and took an age to diagnose - take to a decent LBS.

xhacker

Are your shifters, triple shifters by any chance?

I bet they are and putting them on compacts was common practice by some 5 years ago!

John.T

xhacker wrote:

Are your shifters, triple shifters by any chance?

I bet they are and putting them on compacts was common practice by some 5 years ago!

Not a problem. Correctly set up they work just as well. A few years back they were nearly all for double and triple.

To the OP. It sounds as if you need to make sure you have good quality inner and outer cables (especially the rear loop). It is amazing how many problems are caused by this. Set it all up from scratch using the Shimano tech doc, Sheldon Brown or Park Tools site for how. As said above the limit screws are just that and once set should not need touching again. New cables will stretch and bed in so will need occasional tweaking after a bit of use. If you still can not get a good change at the rear get the hanger checked. The front and rear mechs have very little affect on each other so if you have trouble with both you have 2 problems that need sorting separately.