I have a Giant Quick-e+ 2019 and would like to install either a Alfine 11 speed di2 IGH. My first question is, is it compatible? I've been looking at the measurements and it seems all ok. But when I ask different bike shops I get different responses from ones like "why do you want to do that?" to it will break because it's an e-bike. One shop had a look and said it looks like it would work and thought that a bike like that being a commuter type bike would have been a good match, which I agreed and why I want it.
From the whole e-bike breaking the hub thing, Shimano list a version the SG-S7051-11 being revised with "Improved internal structure for better gear engagement" and "Improved performance for both E-BIKE and non-E-BIKE usage" So I think for a 250w - 500w e-bike it should be ok, especially for my type of riding which is all on road/pavement and almost all flat?
What do people think about this project? Is it suitable? Will I have issues? What other components do I need? One bike shop said I might need a torque arm for it. I didn't know about this as I thought all I need was the correct washers for a vertical drop out.
Any tips or suggestions would be appreciated.
edit: I would be running the hub with either a 42T or 44T chainring and a 18T sprocket. Not sure if those ratios would be ok?