I looks like the original post never posted. So, I will ask again. When upgrading to add a granny gear to to an Ultegra double crank does one only need to replace the crank and brifter, or are there certain chainrings that can be added to double cranks without replacing the crank itself?
Or, does the derailurer need to be replaced as well?
There are a lot of hills here, and on certain of them, I think it would be useful to have.