Forum win!! Congrats on the fix.
Makes sense why many choose not to have a BMS for discharge. High amp BMS’s for discharge are also huge.
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Yeh, community power! This aspect should be highlighted somewhere. At the time I was seeking for information was clear the part that BMS has a constant discharge current, if it is used for discharging, whihc will limit the drained current during hard accelleration if you choose the wrong one. Although was not really clear to me the fact that can also cut the current during brakesm whihc makes a lot of sense now but I discovered it in the wrong way…
Now you’re bypassing for discharge doesn’t that mean if you heavy brake it will overcharge the battery? Anyone know how much overcharging 18650s can typically take? I know lots of Lipos can go HV 4.35V, although not advertised for safety. Not sure about Li-ion.
Yes you will overcharge the battery but only for 1 sec and moreover just the first kms. Better to give a bit of stress to the battery than don’t have the brakes, belive me, I know it! 
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That’s true
I’m using the bestech 80a bms because of the 80a discharge rate. If i should buy a quality bms only for charge (im from EU) what should i buy then ?
I think only for charge you can go with cheap one from ebay or Amazon. Something like 10s 15A constant discharge current. You can by them also from bestech if you trust them more. If you can wait Ali is the way. Otherwise some Esk8 store. If you need names just ask. The high discharge BMS takes a lot of space. Now I have a big BMS only for charging. I do not like.
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Yeah… But one of the main selling points for the bestech 80a bms, is that it has a in built “anti spark switch” with a bypassd bms, i would need to have a separate anti spark , if i dont want to use a simple loop key etc. And this will also take Up space, and given the fact, that many antisparks is known to fail at some points , i think that there is more in to it. From my home, i always need to brake down a hill the first 500 meters, and with a fully charge batteri, and bestech bms for discharge, i have never experience my brakes to fail. This compo is a year old now.
Than perfect like that. I che k my bms cut the current once reach 4.25V so even if I charged to 41.2V for the first km or so if I hard brake it will do it. Probably yoyr bestech has higher threshold (since you can decide it when you buy it) or the overcharge has to last for few second preventing the issue with only spikes.
Edit: anyhow my BMS is way bigger than my antispark. True the second part that they tend to fail. Questin with the antispark on the BMS your board has to stay on during charging?
Than If you change the BMS the only difference is that you need to unplug the loop key often than now, but the space taken is the same. Anyhow if you don’t have problem why change it. I also didn’t have problem the first two month than when I need to brake hard immidiately due to a truck going backwards it failed and I tasted the concrete…
I’m curious what happens in the situation when you don’t have a BMS on Li-ion pack(because I plan on balance charging it with a Li-po balance charger) and you break hard on 4.12v as well or on full charge?
Does the same happen wherein the Vesc will shut itself off to prevent over voltage because the power being generated from the motors braking has nowhere to go?
If that was the case what would be a safe solution for that besides always leaving some allowance like say 90% charge before riding?
If you don’t have a BMS on discharge then nothing will happen, the VESC won’t shot down you will have to be riding downhill non stop with a battery charged at 100% before the VESC triggers the maximum cutoff voltage.