Say I wanted to limit my board to a set speed, how would I calculate the max erpm I want to achieve that speed? There must be an equation for that around here somewhere but I havenât found it.
Interesting I also just had this start happening on one of mine. Havenât found the cause yet. I plan to change the remote receiver first
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@pookybear - Depends on which bolt youâre referring too but M5x20mm Button Cap, M6x25mm Socket Cap, M8x16mm Knurled Tip Screw, M5 Lock Nuts, M4x8mm Socket Cap. If you used Imperial hex keys that could be what stripped them.
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M5 x20 button head. I believe itâs the stainless steel one. No, I have metric tools.
I wanted to know so I can put an order in from Amazon. Thanks!
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@pookybear If youâre trying to tighten the M5 Lock Nut. You want to only hold the M5 Button Cap bolt and use a wrench to tighten the M5 Lock Nut. Doing it the opposite way will strip the bolt 
Opps sorry. Itâs M5x25mm if you want to use a Lock Nut 
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Hey, so when you buy from someone quite reputable on this forum, should I select friend+family on paypal or still select the other way âbusiness stuffââŚ? Some people are real nice and quite reliable so I wonder if I could just select friend+family to help them reduce the paypal fees.
That is entirely up to you. Everyone logical will say pay for a good/service so that you have buyer protection.
I buy from friends here using F&F often with no issue. I will stress that word âfriendâ again. There have been a few scammers that have gotten away with some stuff in the esk8 world. Friends and family certainly reduces paypal fees but you sacrifice the buyer protection.
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How do I get reverse function on my VX1? Its connected to a dual 6.6 plus via UART and a pair of hubs without sensors. I know how to use reverse but it just doesnât change anything
Motor kv times voltage is motor rpm
Motor rpm times gear/pulley ratio equals wheel rpm. Wheel rpm times wheel circumference equals forward speed (assuming 0 slip).
So say you have target velocity of 20km/h, to work backwards convert to km/m to make it easier to get to rpm, so 20/60 = 1/3 km/m (or 333 meters per minute). Say we have 100mm wheel diameter, or .1 meter, multiply by pi to get circumference, .314, take 333 divide by .314 and get 1060 target wheel RPM. If pulley ratio is say 16/32 then 1 rotation of wheel needs 32/16 (2) rotations of motor so 2121 target motor RPM in our case, multiply by 7 to get eRPM = 14,847eRPM for the example case.
eRPM = (speed in km/h)/60 x 1000 / (wheel diameter in m x pi) x ratio from wheel pulley to motor pulley) x 7
Edit my talking it through was right but didnât do the diameter times pi to get circumference of wheel, will correct my example, but need a few to rework the math and edit again.
Second edit fixed the calculations anyone feel free to correct or let me know if I got it wrong going to throw together a quick calc for it too.
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Thank you! Makes sense.
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Whatever you do, donât pick the option âlimit ERPM with negative torqueâ or similar. That option may be gone in recent vesc tool, but in earlier versions if you picked that, it would slam on the brakes once you reached your set ERPM and you would streetface.
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Yes, I have a soft limit set at 80% of the max erpm to reduce acceleration before it hard cuts off. Just streetfaced a few days ago and it wasnât fun.
No, not fun at all. Glad youâre OK!
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what street face feels like
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@wafflejock @Saturn_Corp LoL yes that is the correct way, but I find it much easier to plug my information into the calculator linked from the top of forum.esk8.news.
Letâs say for example it says Loaded Erpm is 38556 and Loaded Speed is 42.8km/h
Then itâs real easy. If you want to limit it to 35km/h then you just use the ratio
38556erpm * 35km/h / 42.8km/h = 31529erpm
Limit it at 31529
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Yah knew this existed somewhere but slow day at work 
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Any chance I could get a list of good esc to use for dual 6374 motors and even an order on best to worst would help a bunch 
Thank you.
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There are some ideas in here
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This is going to be largely subjective to answer since it depends on what you consider good and bad things. Some people can stomach any price and waiting for a quality part, some people want easier to replace individual pieces others want more integration, it really depends on what you want in terms of what is best.
Do you care about being able to configure it yourself?
How important is price?
How important is immediate availability?
Would you rather replace a second ESC or have everything built in one?
Are you looking just at different versions of VESC or across all ESCs (do you know the difference?)
What are the power requirements?
Do you want to run FOC mode (again do you know what this is does it matter to you)?
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