Beginner Question Thread! 2023 Edition

Put the battery total capacity back to 4500mah, that’s not the problem.

Because you’re not discharging through the BMS (at least I hope you aren’t), it has no way to measure how much current has been drawn. The BMS is designed to do coulomb counting, which requires measurement of both input current and output current, and since the output current isn’t going through the BMS, it can’t measure that.

tldr, the battery percentage gauge is never gonna read right in the app no matter what you do when the BMS is bypassed. Just guess based on voltage, or use vesc telemetry instead.

No I’m not using it for discharge, charge only. Would a Bluetooth module be more accurate for battery life? Or that wouldn’t matter cuz since I have battery cap settings on the BMS once it hits that voltage it starts taking the power away when it’s at 90% or whatever, that’s something I don’t understand

Oh wait I think from resetting the values it fixed the gauge cuz now it’s reading more accurately


If you mean a bluetooth module for vesc telemetry, then that should be more accurate, yes.
If you mean a module for BMS telemetry, then no, it’ll be just the same.

I did some research about the bypassing of the bms for discharge only and came up with the following wiring plan:

I would perhaps start soldering the left side from the ct-90 onwards and would try to power the whole system (esc, motor) with a lab bench power supply (because I havent built my batterypack yet) to just set everything up and get some parts moving (if that even works as a battery-dummy). I also just want to get parts moving and see if everything works that I got sent. This is why it might be good to just connect the 3 power phases of the motor as I am still unclear about the polarity of the sensor wires of the 6 pin motor connector.
Just for safety I would ask you to tell me if there is still something wrong with my diagram?
Thanks to the forum in advance ^^

  • add a fuse to the charge port

  • C- and B- don’t need to be 12AWG

Check out the beautiful diagrams thread

Thanks that thread was where I did part of my research ^^
I planned a fuse on the connection between the power supply and the 3mm plugs that lead into the bms charge circuit. This way I thought I dont need multiple fuses for more packs and dont have to pack it in the battery case. Or is it better to have a fuse directly on the pack itself (after the 3mm plug?).

And the C-/B- just happen to have 10AWG wires. The BMS came shipped with them already soldered onto the pads :face_with_peeking_eye:

IMHO it’s better to have the fuse on the charge jack. Each charge jack. Not inside the battery or in the charger, although the charger may (probably does) have a fuse in it as well.

Does current bidirectional still support regen breaking?

I’ve been riding my build for 4 days now, the third day I started to hear the motor making clicking noises. I took the belt and wheel off, praying the motor didn’t get messed up somehow but it wasn’t making the noise, I tighten the belt a little more and the noise went away till today. Not sure what the problem can be, not sure if a bearing is messed up in the wheel itself or I would need a new belt

Yes, it will regen brake down to zero, and then begin using power to accelerate the other direction.

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Is the key vibrating in the keyway?

Doesn’t seem to be

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Weird… I have Apex airs on mine and their stock bushings, both wedged to 35 degrees and I’ve been able to hit 38

30 is very comfortable

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Is it okay to test the system and set the esc up with a lab bench psu in place of the battery pack?

Just make certain the psu can handle the current draw. That’s a lot of amps for most psus

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i was thinking what kind of pus- needs amps, guess i need more sleep

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Edit: scratch that. I realized i did not understand split angles / wedging

More on topic - what material did you go with on your wedges?

PLA+ seems to be just fine, printed at 80% infill, I think I did 7 walls

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I do petg 50% infill and 7-9 walls

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