Front derailleur will not change onto largest (52) ring

[Paulatic]

Is the cable outer getting tired?

[reohn2]

I'm pretty certain it ain't an excessively worn chain.

OK

On the basis that the Stop is unlikely to slip that rules that out.

I'm sorry to labour the point but have you checked it?

I still think the potential problem and solution is with the cable after all by adjusting the cable stop previously I managed to solve the problem although like now it was very frustrating that it was so close but would not move onto the largest ring

Then change and or lube the cable and try it.If you're buying a new cable make sure it's a stainless steel one,they're much slicker,less likely to be affected by water ingress,and also last longer.

[Brucey]

FWIW have seen older stronglight cranksets (with 86bcd?) where the big ring has, over time, deformed outwards so that it may no longer be engaged easily. One thing that causes(/is caused by) that is if the chain ever gets jammed between the middle ring and the big ring.

cheers

[QUIST]

Brucey, As far as I know that has not occurred-

i probably will replace the cable with a stainless steel one although I'd still like to know why it wont go onto the largest ring (after all new s/s cables are dead expensive form my local bike shop...

[reohn2]

Brucey, As far as I know that has not occurred-

i probably will replace the cable with a stainless steel one although I'd still like to know why it wont go onto the largest ring (after all new s/s cables are dead expensive form my local bike shop...

Will it go into the big ring manually ie;operating the front mech by physically pushing the mech over?

A further point,are the pivots worn in the mech,it is 'floppy',does the cage feel loose if it's pushed pull inward outward?

[QUIST]

No the cage does not feel loose or floppy I've not yet tried to push it over

[cycleruk]

Wind the "stop" screw out a fair amount to make sure that it is clear.
Operate the dérailleur by hand to check it will go the full distance and move the chain over. (If this doesn't work then nothing else will until it's sorted.)
Now pull the cable by hand at the downtube to check that the mech' will still work.
Operate the gear changer and set the cable adjuster as needed. You might have to re-clamp the cable at the mech if it has stretched.
Now reset the stop screw to stop the chain over shifting the big ring.

[gaz]

.

[QUIST]

0Ironically enough it was only after the installation of the type of adjusters pictured that i could get it to move onto the largest ring at all!

I suppose the best option is to replace the cable but I would still like to know why it won't shift

[Brucey]

photos?

[mark a.]

Ignore the cable for now. Try pushing the derailleur by hand, as others have suggested.

You seem to be "ruling things out" without trying them first. Thought exercises only get you so far.

[MikeF]

It will not move all the way across just beiny a teeny bit short but this is how it was previously and I sorted it out by fiddling withe cable adjuster not the stop. And as I said it an earlier post it moved straight across earlier this week but would not repeat the action when I tried it again

What is the FR?

Sorry I meant FD not FR ie Front Derailleur. I don't understand your reluctance to adjust the limit stop and ensure/check the FD can move to where it needs to go. If it can't shift across enough, as you seem to be saying, it will never work (properly) and no amount of cable fiddling will do anything to help.

I know you said it used to work, but was it moving to where it should be? Maybe it was being moved just sufficiently to work, but a slight wear somewhere eg chain, chainring, cage itself, cable, means it now won't work?

Is the shifter indexed?

[QUIST]

Mike,

Thanks fir your reply. I'd guessed it was Front Derailleur. It is indexed.

I'm reluctant to move the stop as Itry to work on things like this by a process of elimination if it ain't broke don't ( try) to fix it.

I thought I'd sorted it last night but again it won't change up.

I want to sort it mysdelf but am at the moment just guessing- what I could really do with doing is going back to how it was and working on it from then but I suppose I'm going to have to jiggle about with the index stop and god knows what else until it miracously sorts itself out

[andrewjoseph]

but you're not elimination the obvious things.

[cycleruk]

Wind the stop out as said above.
If unsure then note where the slot is and do 2 turns out. (or make a mark on the screw head)
Then to revert back just wind in the 2 turns.
The stop is nothing to do with the indexing. It's there just to stop the chain going over and off the ring. When the chain is on the ring the stop screw should not be touching the dérailleur arm. There should be a very small gap which allows the mech' and chain to positively position.