I am running a 50/33 on a 5 bolt 110 BCD on both of my road rides. The 33 is a special ring made in France, an engineering marvel. Running a GS derailleur 11/34 cassette in the rear on both. So I would say 17 would be the max or one will run into problems with chain wrap formulas...
Tigermom, what rear derailleur are you running to get the `19T differential to work?
Last edited by bldegle2; 01-21-20 at 09:18 AM.