no idea about FOC, I have no experience with it myself. Where did you see this 6000rpm number?
i thought it was chaka who said that 6000 being a safer speed for both or one of those programs @chaka
aha the first page…found it
Is this under load or spinning on your desk?
This was on the bench. I didn’t have a way to test under load at the time. The max under load for that motor and my weight (220lb) is ~85% of those numbers.
Thanks Bender. I just finished my first board. Im running a 245kv SK3 6364 on 10s with 16;36 gears on 90mm wheels. Its twitchy and hauls ass, but I fear my kv is too high and I’m looking for trouble. Drags me (220 lb also) up hills with no problems. Ill be trying to tweak limits in BLDC today, fingers crossed I can keep this thing alive for a bit, but the more I type this response, the more I think I should get a lower KV motor coming from HK.
Does setting ERPM limits actually protect the VESC completely? And if it does, will it do it at the expense of your skin, chucking you off or removing brakes?
Does anyone know exactly what the RPM limits (Max and Min ERPM) does? Does VESC suddenly cut power? Gradually roll off?
And the flip side for if you’re coasting downhill approaching the Max ERPM.
And the “Limit ERPM with Negative Torque”. Does this mean brakes are applied? At the Max ERPM, or before?
And I noticed in BLDC tool the Max/Min ERPM section’s title is “RPM Limit (BLCD only)” so they don’t apply to FOC?
Holy shit I said “And” a lot, but here’s another one. And in the App->PPM section there’s a soft ERPM limit. I suppose this could keep you safe from throttling beyond 60000 ERPM, but not from coasting downhill faster than 60000 ERPM?
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Found This post by ackmaniac with respect to “Limit ERPM with Negative Torque”:
Thats the parameter. When it is disabled then it simply shuts off the VESC. When it is enabled it brakes when it exceeds the MAX ERPM.
Covers most of my questions.
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coasting down for over erpm limit can kill vesc. tho to do that with my board I have to go 70kph. so not many will break the negative erpm. there was a guy in this forum happened this. personally tho this sounds like urban legend. I set my bar to 65k and free spine many times, yet still riding with. it probably depending on ver of vesc too.
as for bldc goes negative rpm limiting really put me off the balance everytime. It brakes soon as off throttle
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So focbox with 190kv motor and 9s 30c battrey is a good pair right?
It’s okay but 250kv might be a bit better.
Would you not recommend 170kv on 10s ?
Hi guys, i’m working on a first build and have been reading a lot of threads on the forums. I did a dual drive and read the earlier posts that a 190Kv will be best on a 12s. However, i’m using a 6s pack, with dual 6355 190Kv motors from TB. What will the performance be like, as comparing to a 12s?
Thank you Tarzan, so the difference is in the top speed… Not that i’d have the balls to go more than 25km/h anyway
Start with what you have and if your confident enough and have a little practice on the board, simply update the battery. The rest of your system is able to do that 
And you can always limit specs in the Vesc tool.
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so suitable for higher speed around 50kph - 30mph do you think is staying at 10S and lowering gear reduction or going 12S? i have 2 190kv motors, and want to go 12S
hes been gone for ages. its really 6 or half a dozen. if you want to be more safe with electronics 10s is a bit safer but otherwise the differences youre talking about…12s would be a bit more efficient and that’s about the only difference.
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I’m a bumper too @73k across the stars
I got a 213kv with a 2x 5S batteries in a series (so 10S). i calculated 7881 RPM. You guys think this is safe?
also what kind of failures would happen if i exceed that erpm number?
What VESC?