Front Chainring

[MickeyBlueEyes]

I'm having trouble, and by that I mean its driving me feckin' crazy, trying to get the chain to move from front inner to front outer. It happened Sunday morning without warning, it was fine putting the bike away Friday evening. I've tried everything I can think of, to the point where it's either something stupid I've missed or my latest assumption that the lifting pegs are worn too much to make any contribution. I'd love to hear about any issues anyone and everyone has ever had with the same issue so I can go through and tick them off when I've tried them.

Some facts:
Chainrings are Ultegra 6600 SL 50/34.
Derailleur is Ultegra 6600 as are the shifters.
Last night I managed to snap the screw that holds the cable so I took dérailleur off to drill it out which was successful. Whilst off the bike I checked the travel of the derailleur by going to inner and then outer extremes with the limit screws. Derailleur moves smooth and as it should.
I have tried two cables to rule this out. Both functioned exactly the same as the other.

Imagine being on the inner chainring, moving the shifter to shift up and the shifter stops when the chain is just about to engage on the pins. What I do know is that the movement of the derailleur in this position is not being stopped by the limit screw as I have exaggerated this to the point I should see the chain ditch over the top.

There's a couple of things nagging me, have I got the cable tension wrong and this is what is stopping it, or, has the outer ring come to the end of its life. It's probably seen the best part of 20'000 miles so I wouldn't be surprised. I would like to explore every mechanical option first though before shelling out £68 on a replacement.
Cheers folks!

 

[gwhite]

If it was working when you put the bike away then it's probably the front changer winter crap preventing it moving over it's full range.
Touch nothing before lubing the front changer and working it to and fro to see if this does the job......usually it does.

 

[MickeyBlueEyes]

If it was working when you put the bike away then it's probably the front changer winter crap preventing it moving over it's full range.
Touch nothing before lubing the front changer and working it to and fro to see if this does the job......usually it does.

Tried this, sadly no joy

 

[Tim Hall]

What happens if you pull the cable (assuming you have exposed inners) where it runs down the downtube?

 

[jack smith]

Install an in line barrel adjuster and make sure you pull the cable really tight with pliers before clamping

 

[MickeyBlueEyes]

What happens if you pull the cable (assuming you have exposed inners) where it runs down the downtube?

Disconnect cable from shifter and manually pull to see how far derailleur moves? Nope, not tried that. That will be the next thing I try tonight. Cheers Tim, good suggestion.

 

[ColinJ]

I had the same problem.

What happens if you pull the cable (assuming you have exposed inners) where it runs down the downtube?

Doing that confirmed that pulling the cable far enough would get the shift to happen ...

Install an in line barrel adjuster and make sure you pull the cable really tight with pliers before clamping

... and doing that fixed it!

 

[KneesUp]

Has the front derailleur rotated slightly on the frame - perhaps by leaning on something in the shed? It's surprising how much difference it can make.

 

[MickeyBlueEyes]

Install an in line barrel adjuster and make sure you pull the cable really tight with pliers before clamping

Install one where Jack? I have one at the top of the down tube already.

 

[MickeyBlueEyes]

by leaning on something in the shed?

Never lean the bike up, always put it on its stand in the workshop. I've also had the derailleur off and then set it back up again but still see the same results.

 

[MickeyBlueEyes]

.. and doing that fixed it!

Which bit Colin, installing the adjuster or pulling it really tight?

 

[ColinJ]

Which bit Colin, installing the adjuster or pulling it really tight?

I already had an adjuster but I didn't have enough adjustment with the cable as it was so I wound the adjuster in about half way, pulled the cable as tight as I could and then used the adjuster to fine-tune the mech. TBH, I think I need to pull a little bit more cable through because it is taking 2 clicks to shift up to the big ring rather than 1. Maybe I should have wound the adjuster fully in before tightening the cable ...

 

[KneesUp]

I already had an adjuster but I didn't have enough adjustment with the cable as it was so I wound the adjuster in about half way, pulled the cable as tight as I could and then used the adjuster to fine-tune the mech. TBH, I think I need to pull a little bit more cable through because it is taking 2 clicks to shift up to the big ring rather than 1. Maybe I should have wound the adjuster fully in before tightening the cable ...

No! When you do this it is a guarantee that you will adjust it too perfectly and need to slacken it off, which you then can't do without starting again.

You can guess how I know this.

 

[ColinJ]

No! When you do this it is a guarantee that you will adjust it too perfectly and need to slacken it off, which you then can't do without starting again.

You can guess how I know this.

Ha ha!

Actually, my hesitant front shifting problem is probably now due to wear and tear in my shifters. They are 15 years old so the mechanisms are getting a bit sloppy.

 

[KneesUp]

Actually you could sort it with the limit screws on a shifter anyway. It's brakes I've done it on. Several times ...