dual 190kv motors with 20/36 gearing on 107mm flywheels, 10S4P 25R, 80A motor max 40A battery max per focbox. I think it’s the gearing… i’ve always geared for speed, so the torque is never anything too crazy.
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Ahh ok that makes some sense, you have almost twice the gearing (top speed) that I do, giving me double the torque-per-amp.
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Not sure if these will be of any use, but here’s some data from my vescs.
Ooo, how are you getting the data out? I couldn’t get ackmaniac to work…
Just to be clear, you should not run Ackmaniac’s firmware on the Unity.
I used this fix applied to Ackmaniac’s FW on the standard FOCBOX with a bluetooth adapter and ESC Monitor.
Are you running a Unity?
BTW, I watched your videos with the braking sound… same exact thing, you’re right!
Ahh sorry, my mistake. I meant running Ackmaniac’s Android app and getting it to speak via a BT module to the unity. Totally missed that you were testing on VESCs and not a Unity.
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Nice guys, I’ll see if I can do anything about the low speed chatter. To be clear, do you find it to be a small nuisance or is it prohibitive to your riding experience in some way?
Personally, a small nuisance on my setup, if that.
Relatively speaking, having the ‘chatter’ is maybe only 10% worse than what I imagine it would be like if it were not being there at all… but it’s 110% better than locking up completely.
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For me it is a nuisance to the extent that I thought my belt was skipping. I think the sensible assumption though is that these boards are not the worst possible case of it. Any ideas as to what is causing it?
That’s a good point… it can sound like a belt skipping. Does it feel like belt skipping when that happens, or do you just get that impression from the sound?
I didn’t get that impression personally, from the feel… and I know my belts don’t skip, but when they did, it does make a similar sound.
It sounds and feels like a belt skipping at very high speed, ie fast skips. I know I’m going low speed, and so I know its not a belt skipping. It’s also completely repeatable. I bet its a hysteresis problem. Definitely interesting!
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Thanks sir. I’ll test as soon as the SF weather allows me to do so. Can’t wait!
To be honest I would rather have the brakes lock at 1-2mph than make a sound like that. I know what that oscillation in these videos feels like because there is one little tiny spot in my brake throttle that I can force it to make that sound and I definitely do not like it hahah
I have not updated to this fix yet 
still waiting for the bugs to get worked out. I ride this board every single day 
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How exactly do I apply the fix to the fw? Using ack 3.102. Do I need to reinstall the firmware to apply it?
I’d say there isn’t actually much feel to it. It’s mostly audible. Basically it’s switching between duty cycle control and current control but motor amps are close to identical so the feel is still smooth (on my setup at least) it just sounds chattery.
I think I can find some way to introduce a bit more hysteresis to solve it anyways. But if I can’t I still think it feels better on my setup. I’ll take a small chatter sound at 1 mph over sticky non-linear brakes any day. Not really too worried though, there should be a fix.
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Aight well I will keep watching, maybe I will try it out anyway. I can always revert if I don’t like it
[Non-Unity Instructions] TLDR: select bin from the custom file tab under firmware.
Yeah, you need to reinstall the FW to apply it. I’d recommend loading and saving all your motor and app settings to xml prior to the update just incase unless you don’t mind setting things up again possibly. Remember to re-apply settings after FW update.
After connecting via ESC Tool, firmware tab, you need to choose the custom file tab and navigate to the VESC Default.bin that you downloaded for your hardware version from my link above- Google drive, not GitHub.
I didn’t update the repo with the recompiled bins, so you can also clone the repo and rebuild the bins locally if you want. The wrong HW version will probably brick your vesc.
Then click the write button. Once you are reconnected, reapply saved settings you had before. Your low speed FOC brakes should be different now.
this 
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This is great, subscribed
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Hello Guys, I was planning to write this firmware but there is only a link for the Unity not the regulaer Focbox, can someone point me to the right direction?