DOS

I am working on a frinds bike whose front shifter was jammed so she couldn't down shift from big to small ring. She has 10 speed 105 5600 components.

I found all manner of threads about the original 5600 double/triple compatible front shifters having a tendency to jam from over shifting when used with a double crankset, so I was able to diagnose the problem and get the shifter unstuck. The shifter works now, but its probably only a matter of time before it jams again. Are there any tricks/techniques for set up that might prevent, or at least limit liklihood, of future jamming?

headasunder

I am about to set up my tiagra l/h shifter(triple) for a double and plan to use the middle and big settings leaving what would be the lower small ring click redundant to prevent any over shift strain by mishap at the big ring end, I am unfamiliar with the 5600 series but suggest that would be the way to go

dsbrantjr

If you are shifting a double, set it up so that the extra shift position slackens the shift wire instead of the other way where it is trying to shift against the high limit screw. That is, so the middle position of the lever shifts to the small chain ring; then the outer position is the big ring and there is no way to shift against the stop, which is what jams the ratchet.

DOS

So if you shift to the lowest setting in that set up, what happens? Does cable go slack?

dsbrantjr

Yes, which does no harm. It is better than the alternative, which is to shift against the high limit and possibly jam the shifter.