105 Front Derailer issue

[bilton_d]

any assistance appreciated

Front Derailer locked up the other week and wouldn't release.
Released everything off and was working fine
15 miles into a ride yesterday and after a climb it wouldn't engage on the large chainring.
Tried adjusting everything no joy. without the derailer connected the shifters work fine but when the derailer connected and adjusted it will shift across but not engage/lock?

[Jimbo.]

Hitting the H limit screw on the mech before the shifter internals have clicked over, maybe?

[bilton_d]

Tried the H & L settings but made no difference

[RRS_Staffs]

sounds uncannily like what happened to my ultegra one on holiday last month

jammed on big ring momentarily, wouldnt release at shifter
then released back to small ring
could move over to big but wouldnt lock
then tried again and felt something 'snap'

currently back at shop for warranty repair

how old is yours?

[bilton_d]

Its out of warranty

the strange thing is that it works fine without the derailer connected, the shifter pulls and locks the cable, when the derailer is connected the shifter moves the same/full distance but won't lock

[agentnomad]

The Front Derailer is just a spring loaded chain guide.

So if the front derailed is smooth and free to move with just the spring resistance it is fine, so the problem is somewhere else, he cheap option is a rought cable and or outer cable, then it is the sift lever it sounds like it will work fine with you just holding the cabe but you are not pulling as hard as the spring does when connected.

cheap fixes remove from bike and clean, very very clean to remove any grit that may be making is slip.

Other fix involves a bike shop/service centre or a new leaver.

[itsnotarace]

New shifter required most likely, 105 shifters are well known for it