RadCity4 motor surging.

AustinMonster

New Member
I've had a cheap archeer ebike purchased from Amazon for two years now, and I decided to upgrade so my wife and i could both ride. I purchased a RadCity4 the other day, and when it arrived, I noticed something strange happening with the motor. It seems to surge in pedal assist mode. The power comes to the wheel in regular bursts, and not in one smooth supply. The video I took (and subsequent GIF II made from it that i uploaded ) shows that the watts going to the motor jumps up and down wildly.

Is this normal? My archeer didn't do anything like this, and I can't help but think this is not how the engine is supposed to function.

I'm not sure if you can get a good idea of the watts surging or not from this gif
 
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Not sure what RAD is going to tell you, but I wouldn't consider watts jumping from less than 100w to over 400w "normal". They do jump around some (within a range of 20-75w top to bottom?), but not like that.
 
My guess is cadence sensor needs adjustment. Magnets and pickup are not aligned or too much gap.
 
I would ask Rad directly.

I have, they are just swamped at the moment. Took them two weeks to answer a question about shipping times. I figured I might get at least an understanding of what's going on from you guys.

Thank you all, by the way!
 
Was thinking about this, and a screwed up throttle might do something like that. Maybe a bad connection where it plugs into the harness? Maybe try unplugging just the throttle to see if that changes anything??
 
I have, they are just swamped at the moment. Took them two weeks to answer a question about shipping times. I figured I might get at least an understanding of what's going on from you guys.

Thank you all, by the way!
Call them on the phone. Emailing takes too much time, dunno what. But everytime I had to call them, always got someone on the line quite quickly.
 
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