Originally Posted by
bikeinxs
It's a nice idea, but every once in a while we just need that granny gear. What I've done instead is run an 11-23 with a 54-38-26 which means I minimize the shifting between chainrings as there is minimal step. When I do shift between chainrings it's a big drop. Even though the chainring spread is outside the "allowable" for my Ultegra front derailleur, it works ok as long as I keep the cable and housing in good shape. I also found that switching to Durace chain made a big difference in the shifting.
If I went with a double I'd probably try for a 54-34 or some such extreme combination but I don't know how the derailleur would like that. You'd need some agressive ramps on the chainrings.
Those are some big changes on that front derailler considering a normal front derailler is only recommended to take 22t difference overall. You are 28. I stretch mine to 24 and do not have a problem and drop from each chain ring is not excessive. (48/36/24)
And if you go Double- That drop is going to be 20 on one chain ring so the Change in gearing between rings is going make for a larger drop than you are experiencing already.