Originally Posted by
mschwett
in practice, what's the speed beneath which it's just not feasible to ride a road bike up a hill?
to answer directly, 3-4mph? Below that, you'll be walking. And it'll be a 22% grade. In other words, the 52/36 and 11-32 is plenty. You could go with a 50/34 up front if you want a little lower, or go with a "mullet" setup which is a mtb derailleur and cassette with road shifters. Considering you're able to put in 225-250 watts, if there aren't other limitations to ditching the e-bike, you'll be fine.
My ftp is under 250w, and I spent last week at Ride the Rockies: 418mi and 29k ft of climbing. Not a lot over 8%, but when it was, 60-70 rpm with 36-32 was very doable (for me, anyway). Only once did I wish I had the 34 up front, but that's because it was 100*F and it mile 98....