I’ve never seen that calculation, I don’t know how. You just saved me a shit ton of trouble. Thanks mate.
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@Namasaki > 60k/7pole pairs = 8571 RPM How do you know how many poles a motor has? Specifically I am curious if a TB 6355 260kv is to high of a KV to use on 10s3p. And if x2 TB 6355 260kv is too high KV to use n 10s3p.
The reason I am so confused is that my kids board has a x2 5055 280KV motors and 10s3p.
Thanks for the expertise 
260kv with 10s is over the limit when using a Vesc. 7 pole pairs or 14 poles is common for the motors we use including TB’s motors. (Although, I’m speaking of 60mm motors and I don’t know about 55mm motors.) You may be able overcome this limitation by setting the erpm limit in the bldc tool to 60k. And as long as your not going full out at full throttle, you may be ok. Is your kids board setup with Vescs? If yes, then maybe they aren’t riding fast enough to exceed the limit. @chaka may be able to address this question better seeing that he is the expert on this topic and all I know is what I’ve read in his posts.
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Hey there! I can’t stop looking at this diagram and your pictures! I have (2) 5S 5000 mah Lipos. If I was to keep my balance leads for the same reason (testing) would you recommend I get a balance lead to connect from the Lipo balance and then take the individual wires (minus the ground) from both Lipos into the BMS? In my head this is starting to make sense but in practice I feel like their would be some fires 
in my case. Thanks in advance.
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Got another one for ya if you don’t mind! What kind and where did you get the charging port? Man, this is becoming more and more fisable in my head. 2 months ago I’d never imagine I could even solder let alone understand your post! Thanks again 
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The switch is useless but the charge port works fine. This charge port is the small version and fits the cheaper 42v chargers that are sold on eBay http://www.ebay.com/itm/222029867724?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
I used these extensions to connect the balance wires to the bms: They’re really nice because I can quickly disconnect each battery pack from the BMS balance circuit for individual testing, charging or replacement if necessary, although I hard soldered each packs main wires for minimum resistance.
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Beautiful and well thought out! It’s like the matrix, I’m starting to see the code! Thank you bro!
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Open the motor and count the magnets in the shell. This motor has 14 magnets (poles) or 7 pole pairs multiply voltage x KV rating to get RPM multiply pole pairs x RPM to get ERPM
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Good info, thank you sir. I am slowy getting my head around all of this .
Your very welcome, About the TB 260kv motors, I used to run those. They are good motors with a good torque and speed. Their shafts are long enough to accommodate the wider pulleys and belts. They also are well made and come with quality NSK bearings. I ran them at 12s with Hobby ESC’s on 90mm wheels and got 28mph going uphill.(just a slight grade) When I upgraded to Vesc’s I switched to 190kv motors and 10s because I was afraid of causing DRV fault in the Vesc. But, I think that you could possibly run them at 10s with the Vesc if you turn the max erpm limit down from 100k to 60k in the bldc tool. This is only speculation by me for I have not tried it and I am by no means an expert concerning the Vesc.
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Mine is allready at 60k MAX ERPM, I thought that was the most it should be because of DRV issue?
I am running a 6355 190kv right now until my replacement gets here, if I raise it to100k will I get better performance? It’s slllloooooowwwwwww right now 
.
Ideally, I would like to run dual 6355’s, but I am still waiting on my 10s pack and DIY is out of stock on VESC’s for a couple of weeks and I need to get another motor, so Ill probably go with 190kv at that point.
I don’t think upping the erpm limit will help performance. However, your other settings will. Post screen shots of your other settings in bldc tool and lets have a look. Also are you running 10s voltage?
I am currently running 6s (x2 zippy 8000mah 30c Lipo packs), but I am going to 10s when my new pack gets here.
I am really confused by the math regarding the VESC and Motor KV values, mostly because I’m missing so much of the math for a full understanding. So if I have this right…
8600 / MAX Voltage = MAX KV then 8600 / 42.0v (10s) = 204kv so 204kv would be a theoretical maximum that can be used on the VESC. But that is dependent on the MAX ERPM limit being at 100k?
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motor kv means rpm per volt. So, 200kv means 200 rpm per volt. So, 200kv x 42v = 8400 rpm or, 190kv x 42v = 7980 rpm The max safe erpm for the vesc is 60k 8400 rpm x 7 pole pairs = 58800 erpm You could safely run 200kv motor at 10s without having to worry about erpm limit.
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6s voltage is minimum for e-skate and is probably the reason for the lack luster performance. especially acceleration. Upping the voltage to 10s will make a big difference. Your motor max (60a) and batt max (60) are plenty high enough. The only thing, you might try switching from watt control to current control in the PPM settings. I don’t know if you’ve tried that but it may make a difference. I run in current mode myself.
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More on voltage, I have run 6s, 10s and 12s. Even the difference between 10s and 12s is very noticeable concerning acceleration. 10s is smooth and manageable. 12s is very snappy and requires much more caution when squeezing the trigger. 6s is the most controllable and is good for crowded sidewalks like the boardwalk at the beach where speed and acceleration is not needed.
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What setting would I change and how to define the value for that setting if I wanted to run 260kv motor or motors at 10s? Or is that even possible? Is there a method of including the ERPM limit into the formula KV * MAX Voltage * 7 = ERPM?
I have always run 6s up to this point but my range is not great, that’s why I wanted to go to 10s on my everyday board. Eventually I want to run dual motors, but I have some product to buy first.
Thats the formula. KV x V x 7=ERPM Provided the motor has 14 poles. There are some hub motors that have more.
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have you ever tried running in current control mode?
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I think it is possible but I am not sure. the setting is on the first page and you already have it set at 60k. Chaka is an expert on the vesc and could probably give a better answer.
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