Failed build 2 years ago and gave up, desperately need help on second try

Hello everyone, Two years ago, I attempted to build an electric longboard. I purchased the following: 218mm torque board motor mount https:///collections/bundle-kits/products/single-motor-mechanical-kit 190 kV 6374 Motor https:///products/electric-skateboard-motor-6374-190kv Torque ESC https:///products/torque-esc-bldc-electronic-speed-controller BMS from best tech

Luna 36V 4 Amp charger

Case from psychotiller

Controller from miami electric boards.

5 turnigy, 60C 7.4V Lipo Batteries.

In the end, nothing worked for me and it was heartbreaking. I talked for months with Namasaki and other users for help and nothing worked for me. As i was a freshman in college when i started this process, I did not have the funds to redo the board and I was stuck with a broken, unusable electric board. At the present, I do not have an overly abundant supply of funds, but i would really like to get my board working for the last semester of college.

My best guess is that the BMS boards fried somehow and my batteries fried as a result, or the other way around. Hence, I at least new a new set of batteries and BMS. I do not know if my VESC was fried as well, but i cant check as the board has no power. Same with the controller circuit board.

Attached are images of my board and previous setup:

I have spent the last couple weeks refreshing myself on the different aspects of DIY board building and how everything works. It is at this point that I need help with getting new batteries, if I should should go lion this time instead of lipo, where I could get the best deal, etc, as well as if there is anything of my current build I should change out.

For reference, I would like top speed of 30, with a range of 15 miles. This means I would like a minimum of 10s, prefereably >5000 mAh, with a minimum Wh of 250.

Basically, I am still at a loss of why my board didnt work previously and am really anxious about this second time and making sure it is not a repeat.

Thanks for making it all the way through this. I appreciate any and all help.


Start with the simple things first. Check the voltage of each individual battery (disconnect them from the board), if they are all good check the voltage going into the BMS, if that’s good check the voltage coming out of the BMS

By the looks the solder joints are not up to par so maybe a connection is bad, alternatively the BMS may be cutting the connection since the cell voltages will all read as an error (non of the balance leads are connected, please be very careful with with which one goes where)

BTW you’re gonna want to go to forum. since all the cool people are there too


This. please join the new forum, this one is not being paid and we don’t know when it is going to go down


Where are you located? Maybe you need a once over with someone experienced to jump start you on how not to blow stuff up.

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Mcminville Oregon. And honestly, that would be so nice. Its really f’ing hard to find answers to all the questions I have. Like there are only so many answers you can find by searching and asking. Discussing in person would be so helpful. @Skunk has actually been answering some questions I have, which helps.


The oregon gang is creepy. Make sure you wear protection. :slight_smile: you might be able to trade favors. I hear @Skunk is moving.

BTW your parts look nice.


Appreciate it. Hopefully this time, I will work more than once :joy:


Start here. If voltage is below say 3.2v per cell you may need a new pack. You’ll need a multimeter. The harborfreight free with coupon one will work. The health of the packs will determine next steps.

I already know the batteries are dead honestly, I know I need to order a new set. I just don’t know if I need to order new bms’s, vesc, or remote/remote 2.4 receiver. I’m sure the motor still works fine, so I’m not worried about that. I just sucks cause Im not sure if I have enough to replace all 3 if it needs it.

That’s a shame, that was a nice battery setup. I feel like, maybe a good strategy here is to get the cheapest possible battery that will move your board, because the chances of you killing it while you learn are decently high. Once you learn care and feeding of battery packs you can move on to a more $$$ pack.

I would honestly advise not hooking up BMS at first. Do a few short rides (don’t drain the pack down too far, set esc cutoffs conservatively), charge the batteries carefully to like 85% while checking cell voltages manually. Like 3-4 rides. This would be a very simple system, easy to troubleshoot (if the battery was built well).

Then once all this stuff is working add the BMS.

The trick then is what battery to start/test with… @ZachTetra do you have anything horded? :slight_smile:

Just to give some comfort, you can probably get an equivalent esc in the $50-60 range if you get lucky. If you go to the other forum, in a month or two we may have access to a focbox (single) clone for $80, called the NeoBox.

If the BMS is toast you can replace with a small charge-only one for like $20. Likely candidate is the Bestech D140, or a generic red waterproof bms from aliexpress.

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Sorry that happened but I got nothing good at the moment. I’m selling a 6s 5000mah lipo, but that’s nothing for this build so not at the moment…I can make a 10s up to maybe 6p Samsung 13Q in a bit though. I’m not an expert at building packs but it would be good quality and decently safe to use (I mean I’d trust it)

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the 6s might be great for testing, what are you looking to get? OP can resell it for a small loss when he gets his real battery. I guess there’s the question of how to charge 6s without spending money…

I was hoping $50 plus shipping and fees for the pack and a charger for it (no BMS), but I’ve just gotten someone interested on the other forum already

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Yes, I agree it was an awesome battery setup. It would have been high output. And I agree that the chance I kill it is somewhat high, but ive been doing alot of research to figure out exactly what went wrong. Im thinking it was either a defective bms, or defective balance placement. I appreciate the assistance. I agree that

this would have been a good idea in the beginning, but I overshot. And ya, I think that that is the way to go, small, charge only bms.

On a side note, a guy on here who lives close to me has offered to help me figure out my battery situation.

Question though that ive been looking for. What do you do to waterproof your board as much as possible?

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Also, why do some people recommend a discharge only bms and other a charge only bms. Whats exactly the difference/why is one preferred over the other?

Don’t attempt this now. Get your board working for a prolonged period, then look into improvements. Basics first.

charge+discharge bms:

  • big, expensive
  • protects output from overdischarge and overcharge
  • if protection kicks in, power cuts off and sometimes sends you flying

charge only bms:

  • small, inexpensive
  • provides protection only for charging
  • will not cut off your esc, will always have power even if it’s destroying the batteries (many feel batteries/board are cheaper to replace than broken bones/joints, etc).

I’m in Portland. I’d be happy to go over it with you if you can make it up here. I’ve even got some extra battery packs and components sitting around that we could use to troubleshoot.



I have a couple questions that I have been unable to find elsewhere in this forum or the other:

I will be riding my board almost every day to class. Should I allow my batteries to drop down to ~35v before I charge it to get a whole cycle or could I charge it daily to maintain that pre-sag feel? Or is that really bad for the batteries.

Would you recommend the ackmaniac tool or the vesc tool?

Also, correct me if I’m wrong, but a 10s5p q30 battery has a continuous output of 75 amps correct? Or a peak of 100a. And my motor is capable of 80A, and my esc is 50a and 250 continuous.

I was just looking at setting up my vesc settings. I have to base everything off of my esc then cause it’s the bottleneck? So the motor max would be 80a, the motor min would be -80 (?), peak 250a, batt max 50a and bat min like -20 (?). And what’s your thoughts on foc vs bdlc? Sorry, alot of stuff all at once. Just tryin to review my stuff before we get together.

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And how do you think this bms would work?

lithium ion doesn’t have memory effects like ni-cad or nimh, so you can charge it whenever you like. However, lithium ion does degrade when stored full or empty. So try to top off right before you ride for maximum cycle life. You can also charge to 4.1v/cell to roughly double cycle life, but doing this will not give bms an opportunity to balance the pack, so at least once a month give it a full charge.

Pros and cons. vesc tool will have all the latest and greatest, and all the up-to-date support and documentation will match. On the other hand, ack’s version is kind of frozen at one version, so it’s very well understood, works with the ackmaniac android app, and some would argue the newer features of vesc-tool are not really significant. You can try both and decide for yourself. I prefer ack, but every day as vesc tool gets improvements, the scale shifts toward vesc tool.

internet wisdom is 30Q is good for 20A discharge. A 5p pack can do 100A if built correctly. But not many motor/esc combos can extract that much power. For example with settings at 50a battery per focbox in a dual drive 6374, I’m only about to pull 70a from the battery total.

Start small here and work up. You can use the factory defaults I think. You’re on a single 4.12 vesc. I think a safe motor max is 60a (but start at 50a). Battery max, safe is 30A. I don’t think it’s safe to set more than 35A (but you may want to try higher).

This is a simplification, but motor max influences torque at low speeds. battery max influences torque at high speeds. You get the smoothest control by setting both to the same number. But typically motor max is set quite a bit higher.

FOC vs BLDC, on your 4.12hw esc, do NOT use FOC. I repeat, do NOT use FOC. It has a very very good chance of frying the drv. Also do not do 12s. The reputation of torqueboards 4.12 is anything more than 10s BLDC is danger danger.

Generally, BLDC is loud and powerful, FOC is quiet and more refined (and also makes the FETs heat up more). FOC has gotten more attention from bvedder, so for example, sensor support is better in FOC. On newer good quality vesc, most people run FOC.

With your story, get your board running for a few rides before thinking about BMS. :slight_smile: Keep it simple, work forward in small steps. When it’s time, try to search here and on the other forum, for a popular BMS.

Finally, you should hit up @GeraldSwerdfegger with his generous offer! Meet up, buy him cookies, show him what you’d do and have him teach you all the places you messed up and would blow something up. :slight_smile: