Help with Stock Onewheel XR conversion using Ubox 100A 80V

Hello!

Im pretty new here, and I’ve got a slight problem. I’m looking to convert my Stock Onewheel XR into a VESC. I’d like to use a FOCer but they are prohibitively expensive. I am looking to use a Ubox to replace my stock controller, and I’m keeping my stock battery and BMS. I would like to keep the costs low, and I think keeping the BMS and battery would be a good way to keep the costs low.

I’m trying to find a wiring guide or some sort of tutorial on replacing the controller with the Ubox, however I only see SurfDado’s video on the Ubox which doesn’t really explicitly show the wiring and how he did it, or the video by WillD is for the Pint X, while I have an XR

Does anyone have any wiring diagram or tutorial that I can follow that can help me figure out how to put in the UBox?

Also, on a side-note, I would like to keep the original plugs for the footpad, motor and battery. I was considering de-soldering the ports from the controller and adding them to the Ubox, if that’s possible.

you can still follow my video and any of the Little FOCer / Flowglider wiring diagrams. Wiring diagrams are not VESC model specific because the connector ports are pretty much standardized.

And sure, do reuse the existing ports, except desoldering the giant 16-pin Molex is not for the faint of heart…
But, keep in mind that you can resell your working untouched XR controller for $100+ or way more if it’s a 4208/4209, Even the wiring harness will find a buyer for $100+ on FB. Then you could just buy the pre-soldered connectors from makerspev which would be much cleaner. They are all compatible with the LFOC, and you don’t need the power button of course.

The battery should be converted to charge-only, there’s some posts on how to do this… but that’s not UBox related at all.

sounds good!
Also, the controller is a 4212, so it’s probably not too valuable, plus I’m keeping the battery box itself. I think i’d rather desolder the molex connectors

But thank you! I was worried that the FOCer and UBox would have a different set up

Back here again!

I haven’t found a good explanation on what it means to make the battery charge only. Does that change the functionality of the BMS in any way that could be of concern?

I am also going to probably just snip the legs on the 16-pin Molex if it gives me too much trouble.

Following. I just bought a nice 4212 XR. I’m not 100% sure it’s possible, but I was thinking I could use the stock BMS and an OWIE with a CBXR and cheap VESC controller to get the most bang for my buck. I could start with a ubox 80V and the stock battery, then add a bigger battery as needed.

Charge only means that the controller doesn’t read individual cell voltages, temperature or other battery information. The BMS can still balance the cells, so it’s not super important. The controller and VESC app still read your overall battery pack voltage, so you can gauge battery life.

1 Like

I know this is an older post but I just finished my XR conversion using the Ubox 80V, stock XR battery and FM BMS. I chose to keep my 4208 controller box unopened and print/use the flowglider universal hobby box from thingiverse. It is a tight fit but it works! I have noticed a significant increase in torque with a vesc’d but otherwise stock XR, if I had to guess I would say low speed torque is almost double what it was. Currently I have my FM BMS as charge/discharge but I am planning on eventually throwing in an 18s battery with an accompanying BMS and selling my stock BMS. If I do end up doing that it may be worth going to a LFOC for extra power though. If you haven’t done it yet and have any questions about my setup I’d be happy to help!

hey, thanks for the follow up!
I managed to get it all figured out, I just had to ask a few people in DMs and ask a few clarifying questions

The FM controllers (Xr, pint/x, GT, ect.) all limit their amperage output far bellow what we run our motors at. For the XR, their using a connector for the phase wires that can only handle up to 30 amps sustained per pin. We usually set our motors to have a max 100 amp, so that immediately is more than three times the amperage limit.