eBike technology explained

Hey everyone!

Been lurking for a bit, but finally decided to jump in with a topic that's been on my mind, especially with all the cool custom builds I see here. When you're piecing together your own eBike, whether it's a commuter or a full-suspension trail beast, understanding the why behind certain tech choices feels crucial.

So, for those of you who've built your own from the ground up, what's one piece of eBike technology you found surprisingly complex or surprisingly simple once you dug into it? For me, decoding the nuances between different motor controllers and their impact on ride feel (especially for torque vs. cadence sensing) was a real rabbit hole. Any insights or "aha!" moments you'd like to share on how specific tech works in your custom setup?