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Radwagon Losing Power - HELP!!!

Started by pearlbeer, June 04, 2023, 03:53:50 PM

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I have a 2019/2020 RadWagon. It has 26" wheels. 3,000mi, well maintained, no major issues, water damage, extreme temps etc.

The bike works fine, powers up with no error codes, but loses power after about 10secs of PAS or throttle at any level. Goes up to proper wattage, then just drops to zero. It seems to fix itself if you power the bike on/off or pedal for a while, but then loses power after 10secs. The LCD display does not indicate anything abnormal. This issue can be identically repeated over and over.

Here's what I've done (the same EXACT issue continues)
- Does not seem to be a bad connection/wire since it is easy to repeat

- Unplugged, replugged brake sensors, but issue repeats

- Check voltage coming from battery and replaced both fuses

- Replaced the Controller with a NEW one from RAD. (Actually two as they sent me the wrong one first)

- Replaced the entire motor/wheel assembly with a NEW one from RAD

- Borrowed a friend's battery to check if it is something with the battery/battery controls (same problem)

I'm stumped. I guess the wiring harness or the head unit LCD could be the only other things I could possibly replace? At this point, I've got enough stuff to build up a new bike!?!? I can return stuff I don't need to RAD, but have not been able to isolate (and fix) the issue.



at first i thought maybe battery but you have eliminated that. 

have you run the bike with the brakes sensors off?  it might be a the brake lever itself that is bad.  it might just be one side. so disconnect them both at the same time.  ran the bike and see if the problem continues.  then connect one at a time test then connect the other one.   removing the sensors still allows you to brake.  the sensors tell the controller to stop power to the motor. 

have you looked at the pedal magnets to see if they are still intact?  i doubt it is this since throttle is the problem too. 

if it isn't these then maybe the wiring harness has somehow gone bad.  not sure how it could go bad just sitting there unless you have dropped the bike. 


Disconnecting brake sensors sounds like a good idea.

A tiny bit of moisture in the Bolton controller of my Radrunner would cause the motor to die intermittently. There wasn't enough moisture to detect when I opened it, but a hairdryer would fix it for the time being, and sealing with RTV was a permanent solution.

If your display has similarly sensitive circuitry, maybe a tiny bit of moisture got in. In all your riding, maybe a seal developed an air leak. Highly humid air could cause condensation under the clear panel of my Bolton display, although moisture didn't cause that display to act up. Sunshine would dry it.


Did you ever figure this out? Ours just started doing this.