Superflux Motor - Issues/Crunching/Vibrating, No Torque

Hi everyone!

I went for a quick ride on my board last night and got dumped after a curb nudge. Thankfully, I was only going about 3-4 mph, so I didn’t fall.

I’m seeking some help to sort this problem out. Thanks in advance.

My build: VESC 84v
-TFL Varails, Straight Rail Config.
-Makers PEV Little FOCer 3.1, Flowglider Controller Box
-Fungineers Superflux V1
-The Board Garage 84v Battery

My build only has approximately 100 easy miles. I’ve treated this board nicely, and only do the occasional curb nudge and curb drop with it.

The issue: After a curb nudge and during the curb drop, my board lost all torque and just freewheeled while the motor made loud crunching sounds and strong shaking. I had to carry the board home, all 36lbs of it.
The motor spins when off the ground, but if you apply any friction to it, it just crunches and shakes.

Video here:

Any ideas where I should start troubleshooting?

This is what I plan to do in about an hour, unless someone in here chimes in with something different.
-Redo Motor Wizard/Config. and recheck Superflux motor.
-Replace motor with a Hypercore motor, run Motor Wizard, and recheck.

Could this be a hall sensor issue?
Should I take a peak at the stator?

Any and all comments, suggestions, ideas welcomed.

Thank you!!


I was just filming a close-up of the video (for better visuals and audio), and it started working again.

Umm… That’s not good. Now, I won’t know what was causing it, which makes it super dangerous. I normally ride at around 22-25 mph, and having that motor give out at that speed is scary dangerous.

Video of my surprise here:

Now, more than ever, I need your help in diagnosing what may have happened.

Something may have been loose?
Last night I took off the footpad, undid the footpad and hall sensor bullet connectors (in case something was loose), and re-connected the battery and motor connectors. This did nothing, as you can see in the first video. From the first video to the second… all I did was reposition the camera/phone, and tried it again (never even turned off the board), and now it works. Scary.

Any thoughts?


Did you ever find the culprit? I am having a very similar issue that is just as unpredictable… I assume it’s a problem with a loose hall sensor wire or possibly a bad solder joint within my vesc. When I first loosely assembled and tested my control box it worked perfectly. I then assembled it fully to find it not working anymore. Many hours of trouble shooting later it just started working again. Went 30 miles with no issues. Just went in today to start adding lights and it no longer works. I’m using a Ubox 80v. Any suggestions would be greatly appreciated!

Hi, Ryland.

I haven’t had this issue again since I made that video. I’ve put about 350 miles on the Vesc since then without a hitch. So, I was unable to troubleshoot the issue, as I couldn’t replicate it. If I had to guess, I would say it may have been a loose connector pin on the hall sensor plug/connector.

Good luck, bud! Let us know if you find out what it is.

Your problem on the Superflux V1 may be the motor end cover rubbing on either the hall or phase wires, there is very little clearance between the wires and the end cover.
I had a problem with my end cover rubbing through one of the hall wires.