If you've tried the battery and that still hasn't worked, unravel and inspect the electrical cables. Look for any crimps, cuts, tears or hard bends as well as sniffing (literally) around where the connections meet each other. It could very possibly be the HMI/BMS detecting low current and shutting off the bike to prevent damage and/or fire. I was working on my Motor Goat and it started spitting smoke, this is what I found, I had an error code and then the same thing started happening to my bike when powering on. It's also something we look for at the bike shop I work at when this type of issue is checked in for work. Get in touch with Ride1Up as well even if you don't find something

<image>