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
Just thought of something So we’re all on the same page, were testing on the bench with the drive system hooked up right?
this is so strange idk even what to think of it. did TB really sell a 190kv batch without knowing? because then it would be the only VESC-compatible 12s sensored motor for this size available…
I tested without any drive belts on the bench. Also, you will reach you calculated top speed if it is in 20-30mph range. I do not see much loss in efficiency until I reach about 30mph.
@WrinklyWink definitely a plus!
I’ll test this evening without the belt to see if there is any difference I’m just curious
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Vedder and I discussed the ERPM limitations of the VESC yesterday and he confirmed some of my findings.
At high erpm there are few switching cycles at each commutation and therefore few adc samples, which makes it difficult to track the rotor. If sync is lost the current can rise very quickly, which can cause failures easily.
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I always thought higher voltage =
- less amperage used (e.g. 17 amps vs 20 amps) (greater range)
- less heat (therefore less damaging during hot summers)
and both of the above leads to more performance headroom. One could also lend the headroom towards a higher torque pulley system. Wouldn’t that bring the ERPM limits closer then? I don’t find it wasteful.
I tested it out and with and without the belt on and the difference was Almost indistinguishable, just slightly lower ERPMs with belt on.
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@WrinklyWink We are talking purely about motor rpm and erpm in these calculations. Luckily these calculations lend themselves well to the common gear ratios resulting in a very usable range of power.
You could lower your gear ratio to get more torque on a system with high erpm but the motor will still be running inefficiently at WOT.
Under your warranty page:
What do you mean by “rigorously,” if you don’t test for KV? Do your strict quality controls not include the KV you advertise?
I’m still waiting to hear back from your testing or an official statement about your wrongly advertised motors.
Stop puffing.
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