Rear mech changing problem

[fossyant]

Do not trust an LBS...... !!!!

 

[4F]

Since when did any mech's tension fail...??

Does the mech have any major 'bush play' - i.e grab hold of the bottom of the cage and wiggle - is there any big play....... My old DA 7400 suff has none, my Ultegra has a 1-2mm play, my old battered Deore LX has lots more, but it all still works....

Does the mech spring back if you 'twang it' - if yes OK......

Cables first, mech then duffed changers !!!!

Both cable inner and outers replaced and lubed. With the chain off the mech was lubed and nothing is in it obstruction play however the tension just feels very weak. I took it to my LBS who to be fair knows his stuff and just mentioned shifting problems and did not mention about the tension as I did not want to put ideas into his head beforehand. He said pretty much what Spandex said in the 1st reply on this thread ie tension very poor and that I should consider changing it. I have compared it to my sachs huret on my other bike and a 105 mech that I have got kicking about and it feels very weak in comparison.

 

[gbb]

FFFF, have you had the rear wheel out ?

I've just been sorting an old Sora clad bike out and had a devil of a job getting the rear gears set up. Its not like i dont know how...but this one seemed very obstinate.
After about 6 tries...i wondered if the wheel was aligned correctly. Took it out, put it back in (taking care it was straight)....and it set up straight away

 

[4F]

FFFF, have you had the rear wheel out ?

I've just been sorting an old Sora clad bike out and had a devil of a job getting the rear gears set up. Its not like i dont know how...but this one seemed very obstinate.
After about 6 tries...i wondered if the wheel was aligned correctly. Took it out, put it back in (taking care it was straight)....and it set up straight away

yep been out several times

 

[swee'pea99]

When I had this problem, someone suggested oiling the cable where it ran round the BB, and that solved it straightaway - but since you say you've disconnected the cable and it still feels weak, that can't be it. Can you get at the spring and physically distort it? Bend it in the direction it should be pulling, so it pulls harder? Bit drastic, but it might work. Kill or cure I suspect. Otherwise, it might be time to stop throwing good effort after bad and just buy a replacement off ebay. Something like this perhaps? Good luck.

 

[Jonathan M]

It's the mech , spring tension not so good and confirmed by my lbs
and new campag 8 speed rear mechs are a thing of the past.B)

So as far as I can see my options are:
2nd hand 8 speed mech and hope tension is better than what I have
9 speed mech (my lbs says this should work)
New 10 speed groupset (not really an option at the moment)

Any other suggestions / comments ? , for example is there anywhere that can replace springs on old mechs ?

FFFF, I'm not sure that a 9 speed mech can be an option on a campag 8 speed bike.

While Shimano tended to ensure 7 to 8 to 9 speed compatability, Campag have, for some reason, not always put this in place, and example being in the change between 2000 to 2001 when Campag changed the cable pull, meaning a post 2001 mech wouldn't work with pre 2000 ergos.

Having said that it is campag, so is likely to be serviceable, and http://www.italiancycleproducts.co.uk/ are the UK Campag service centre. Might be worth a speculative e-mail giving them details of your mech, asking about repair possibility but also what mechs currently available may work. You'll need to have a good idea of how old your kit is.