Another highly accomplished Di2 equipped
local tandem team tried the XTR Di2, and
came to nought.
I just got Campy EPS on my BMC half-bike. It's great, I love it. So effortless. But I'd not consider it for my tandem
at all.
Shifting effort pales in comparison to
pedalling effort. In the Bay Area environs we share there are steep hills like no where else. Just
our little ride yesterday , we looking at
grades of 13%. They
abound around here. Our ratio of 30 front, 32 rear takes care of these. On the top end we retain 52-11. A double (50-34?) with a cassette the size of a manhole cover, with a K-Edge RD cage, may do that, but with jumps that'll have you warning your stoker with a shift. And that'll still be limited on the top end. I don't want a cadence a little too low or high, I want it right on. I get that with a mechanical triple, and but not with a electric shifting double.
Check out the differences here, between 52-39-30 with 11-32 and 52-36 with 11-36. You can make adjustments, eg. different chainrings . The double even witn 11-36
still doesn't have the low gearing (.938 vs. 1.0), but my what big jumps your cassette teeth have!
