50.3v to be exact, but yes a fully charged 12s li-ion will be about 50v fully charged.
Thanks for clarifying it. btw any news about those new motors?
They are in Ohio right now, I should have them by Thursday. I need to do some testing to be sure they perform before finalizing the order for the first batch, this was just a sample run. We are going to do some minimal branding with motor specs etc.
Sounds good man:thumbsup: keep me posted.
I found this very informative so I checked it out in VESC active monitor and found my actual measurements much lower than the pure calculations you have above.
230kv TB 6355 motor at full throttle in BLDC 6s is 32,000 ERPM 9s is 48,000 12s is 66,000
in FOC 6s is 30,000 9s is 46,500 12s 61,000
It seems that 12s in FOC for my 230kv should be perfect but I’m probably missing something
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If that motor is actually 230kv than you are lucky it is still working. I ran a 245kv motor on 12s and it caused a drv failure, full disclosure is the VESC was twitchy to begin with which is why I sacrificed it for science.
@Bender I just ran my TB 230kv motor and you are right, it is showing the same results as my 192kv sk3 so it is not an actual 230kv motor. I double checked by running an sk3 149 kv and a few others and the all gave the erpm values expected so the TB 230kv motors must be 190kv.
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Very interesting… That makes sense Thanks so much for checking I really appreciate your contributions to the forum This info is invaluable, especially for people to be able to design systems that work reliably
So it also depends if you are running in BLDC or FOC correct ??
Another question Chaka ,…do you always charge your cells to full capacity 4.2v ?
Does that diminish cycle life ??
that seems kind of sketchy… i wonder what’s up with that.
back on topic: i’m working on a 12S4P liion build, dual 190kv 63mm cans. Hopefully i’m not bumping up toooo close to the edge here. i figured 200+ would be too much, even splitting across two motors.
This is very helpful info and a great guideline.
No, not really, FOC will knock a few thousand rpm off your top speed but it has the same erpm limitations from what I understand.
I tend to do full charges each time but it will give you more cycles if you only charge to 4.14v per cell. For me it makes better sense to abuse my gear and see when and where it fails.
@longhairedboy It is actually kind of a plus in my opinion. 190-200kv works well for kids and total beginners @ 6s, a good all around board @ 8s, a rocket ship @10s. @12s the extra voltage is wasted and you only exceed 60k ERPM with a tail wind or when going downhill so it is better to drop your KV down and keep that headroom.
I should add that I have only experienced the 60k wall when running 190-200kv motors @12s. Traveling at around 32-34 mph.
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Another detail I should add, you can push the kv up to 200kv @12s but the top end will feel weak. It will have good mid range boost but it will taper off as you approach the max velocity. If you calculate based on a 60k ERPM max instead of 100k the power and boost will increase at a fairly constant rate giving you that freight train experience.
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@chaka what does 60,000 ERPM translate to in mph with 83mm wheels and a 15/33 pulley ratio? I left my TI 60 at home next to my typewriter.
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Around 30-33mph or up to 36mph using a 3.8v cell voltage in your calculations.
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That’s actually about damned perfect. I might just set that as my limit if its not the default already. I can’t recall off the top of my head what the default is, but the guy i’m building the board for wants it capped at 35mph, and i really didn’t know if it would do 35 on its own anyway given other factors besides actual and theoretical component limitations, even on a full 50v charge. But if adding this keeps things in the comfy zone for sure, then i’ll add it to my checklist.
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Wow… that’s pretty odd for that KV. They specifically stated it was tested. At least it’s lower than higher 
It does seem like 230KV though. I will have to start doing more testing. Thanks for noticing guys.
Great post though Chaka. Thanks for sharing.
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do you think that would apply to the DIYes 6374 230KV 3200W as well?
@zool774 I think the batch that Chaka and Bender have might be an old batch but I’m not entirely positive. The best bet would be to test as Bender and Chaka have.
Do not tempt me! That would be an awesome build! Do you think you could get away with some 60A ESC’s as well then? Otherwise 4 VESC’s will become a bit expensive!
I just bought mine in April Just FYI
The good news is the performance is great! I’m getting 15mph on 6s, 22mph on 9s on a single drive and I’m 220lbs 15/36 gear ratio and 76mm wheels
If it’s a 190kv that’s close to 100% efficiency according to the esk8 calculator If it’s a 230kv its 80% which seems more realistic Very strange