Front derailleur stops are the little screws (usually) on the bicycle front derailleur that limit the travel as it moves back and forth to accomplish a shift.
– Shift the front derailleur to the small chainring position, then loosen or disconnect the front derailleur cable.
– Shift the rear derailleur to the biggest cog.
– Set the front derailleur “LOW” stop so that the chain just barely does NOT touch the derailleur cage on the inside surface when pedaling.
– Adjust the shift cable (tighten it) so it is just barely not tight in this position.
– Shift the rear derailleur to one of the middle cogs.
– Adjust the outer front derailleur stop — for the large chainring — till the chain shifts up nicely but does not project over.
– Adjust it to allow some (just a little) overshoot (meaning when you push the shifter lever all the way, the derailleur will move out to the stop, and when you relax force on the shifter lever the derailleur will come back slightly. That allows positive shift pressure on the chain against the ring when shifting, but as the shift completes, the derailleur comes back to proper chain line setting.
– Be careful that you don’t allow too much overshoot because the chain may then shift right off the outside of the ring onto your pedal — which is obviously not acceptable.
– Cable tension must be balanced so there is sufficient slack at the low side, and the cable tension is right to hold the derailleur cage positioned properly for the big ring.
Front derailleur adjustment has been described as a “black art”, so don’t be disappointed if it takes a few tries to get it right. For more information, please see Front Derailleur Adjustment on our support site.