I have a 2020 Rad City with a noise I can't diagnose. It is a cyclical noise from the rear. It is there all the time while riding and not associated with pedaling.  I applied light braking and it still occurs. I put the bike on a rack and it is not heard with the motor turning with or without pedal turning.  Only seems to happen with my weight on it when riding.  I don't see any obvious clearance with the rear fender, but sounds like something is rubbing somewhere!  Any advice appreciated.