does anyone know why this 11s bms has 13pins. it should be 12 right? 11 cells plus b-?
Could actually a 13s bms but should still work with 11s just ignore the 2 extras. Someome correct me if Im wrong.
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@IndianGummy @yelnats8j From what Iâve read about bms systems, I dont believe you can ignore âextrasâ as they will still count in the balancing and since they dont read voltages, it will be the same as if they read undervoltage or 0v. Now someone correct ME if Iâm the one whoâd wrong 
EDIT: THEREâS NO HARDWARE ON 12 AND 13
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This is what I was just going to say. They save major cost by using the same board and just leaving off components, if you wire it how the diagram suggests, it will work out fine. Sometimes they do odd connector splits, probably because they use the other connector in another device, instead of buyng yet another one to accomodate a weird voltage like 11s
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Lol Iâm blind. I was just confused because the wire harness also had 13 wires.
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I suppose they were lazy lol, was it a cheap one? Easy enough to just pull the pins out of the harness if need be
Its from bestech so i trust it. i guess they turend lazy.
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Hahah yah theyâre good, whatever I guess!
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Honestly theyâll probably be pretty comparable to each other. Those wattage numbers are just the maximum they can handle, thereâs nothing wrong with running them below that.
The only thing to check is that your KV and battery voltage wonât cause you to exceed your controllerâs maximum safe ERPM. Generally sub-200KV is good for 10s, and for 12S you want even lower, like 160 or 145.
0.1v isnât the end of the world. If you have a charger with adjustment pots inside Iâd still recommend tweaking it down a few points just for cell longevity, but it wonât immediately blow up or anything.
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Anyone have any idea why this is not working anymore? I have looked and canât see anything obvious wrong.
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I think it went so poof. You mustâve thought it was anodized char texture.
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Big noob question:
!!!BMS!!! ---- HAVE NO IDEA WHERE TO START ----
â> Which one to get, why? (Reliable, affordable, noob-safe) for li-ion18650.
Thanks guys 
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You will probably learn a lot from searching here on the forum with the little magnifying glass, try searching BMS, BMS wiring, BMS options and such. Lots of information to read!
As for now, my personal preference is either Bestec or SuPower (batterysupports.com) both of these places have a good reputation for reliable BMS units. I have the SuPower ones running in three boards right now with no issues. Additionally I have one Bestec d140 running in a 10S build. Custom units like the DieBie BMS also exist but are quite hefty in price. Some of the ones you will find on Ebay are legitimate but a lot of them do not have the most important feature: cell balancing. It is important to have this feature in order to end up with an equally charged battery pack.
As for noob-safe, it is hard to wire a BMS without doing some reading first. When I did my first one it was very confusing. Ultimately it just came down to closely following the included wire schematic, but I had to do some reading to find that out.
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Only make the belts tight enough so that neither one slips when braking at medium speed going down a steep hill. Yes, same tension in each.
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Go through these two threads: Is DIY right for you? and The battery builders club
Once youâve read through both of those in their entirety, come back and ask more specific questions.
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@b264 is such a know-it-all and elitist
I just use old washing machine v-belts and pulleys. To be honest, its easier to make your belts out of superglue and rubberbands, but i have access to lots of old washersđ
Does the xmatic app works with the flipsky nrf module? I read someone that it couldnât but then in the description of the app it says that it is comptible with nrf51.