I upgraded from 11 to 12 speed today on my eR9 equipped bike. By:
- Changing the cassette
- Changing the chain
- Adjusting the gears in the app
That's it! This is such an underrated feature of this groupset (and the Wheeltop one too).
Why go to 12 speed? I wanted to try the lightweight Goldix monoblock steel cassettes, as recommended by jonathanf2 on this forum. Those cassettes are available in both 11 and 12 speed, and I figured 12 > 11
![Grin ;D](http://chinertown.com/Smileys/default/grin.gif)
I can also confirm that 11-34T, with 50/34T at the front, is at the absolute limit of what the derailleur cage can handle, so max capacity of 39. And the chain length has to be
spot on at that setup. One link more, and there's too much slack in small/small. One link less (which is what I did at first), and the chain runs nearly straight when passing through the jockey wheels. And my B tension screw has only a few millimeters of additional travel left.