best way to seal the opening for motor cables? Besides cable glands or liquid sealant?
Bungs/grommets?
hmm i think those would work. I want to have as tight a seal as possible to limit dust/water from getting in. But i think glands are too big; thanks!
Make a hole in the enclosure just big enough, then epoxy a male (with the prongs) MR60 connector through the side of the enclosure. Make sure it points as far upward (toward the deck) as possible for best results.
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What Brian said. Or, you can get multi-hole cable glands, and run all (or at least all of one side) your motor wires through one gland rather than needing six or eight of them.
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@Jujo this is a good start point. Motor max (phase current limit) will be hit until the duty cycle at which it would cause battery max to be exceeded, then it will begin limiting at battery max as the speed continues to increase.
The first third the limiting factor is motor amps, as you continue to increase rpm then the middle bottleneck is battery current, and finally you reach a voltage bottleneck at the end.
It’s a bit more complicated than that also, because wind resistance goes up steeply once you start going fast, so sometimes the peak of motor output can’t be reached in practice because there simply isn’t enough power to overcome drag, so you may actually only climb halfway across the chart. It depends on your gearing and all manner of other things.
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Alright quick question. How do we prevent imminent esc failure as we’re free rolling down a hill at about 35mph. Assuming maybe 80% charge?
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Have a {motor Kv / wheel size / gear ratio / ESC max voltage} that won’t cause any limits to be exceeded.
One way to do that is to use an ESC that is rated for more volts then your battery, the higher the margin the better, and don’t use a setup that approaches the erpm limits of the ESC,
The easiest way is to setup your ride to reach a powered speed that is significantly faster than you will go.
On an example setup with a 12S4P 30Q with dual TB6380 190kv, 175mm wheels 18/60:
It should reach somewhere around 39mph under power and somewhere around 50.5mph on the bench and max out around 57kerpm on the bench.
I would feel comfortable pushing that downhill all the way to almost 50mph but no further. Most controllers we seem to use can do 100kerpm I think. Unity and single-MCU “dual” models excluded, I am not sure about those.
If you really want to feel safe then lower that series count to 11S and use that Max Speed it lists (46.3mph) and don’t exceed that on a 12S battery.
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I will read it later today at work. It’s like 1:36 am rn lol. I’m just trying to break my speed record and I wanna make sure everything is tuned properly. (I know. Conservative settings for a speed board? Pfft) But I don’t want to crash due to failure of parts due to settings
Thanks @b264 will definitely read up more on that later, but a few days ago, you suggested you would set absolute max current AT LEAST 150A. Why is that?
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I’m very, very sure that was for absolute max current value
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Oh yea sorry, thats what I meant. Lemme edit
I’m assuming it’s set to an unreasonably high value so that our esc doesn’t shut down or some shit?
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Yep. Things tend to spike in “transient” conditions but for a few miliseconds it’s more than ok. If that value is too low you get overcurrent faults every time you do something more abrupt with the throttle or brake hard. If you gotta brake and get an overcurrent fault you get no control for a while which is baaaddd.
Absolute max won’t let you pass the mosfet amp rating inside the esc anyway. If the mosfet is a 150A one, that’s how high it will let you set it
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Absolute Maximum Current is the value it will fault at, which cuts your brakes. You want that high.
Those are millisecond long transients
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Thanks a lot.
I guess 2pin is the way to go?
PS: You’re my hero!
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What geardrive system would let me hot-swap between thane and pneumatics?
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I’m not sure what your idea of hot swap is, but it’s the same with belts where you’d have to remove the adapters. So I guess all of them and none of them? 
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ah damn, ok , maybe not hot-swap lol. more like labour-intenstive swap then like which will allow me to use thane and pneumatics? i ask bc i inquired into Moon’s geardrive and he said they only really work with minimum 6" pneumatics, which gives a 22mm clearance, so thane wouldn’t work.
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i don’t think there is any gear drive that is small enough (YET) to work with even TB110, unless u don’t care about clearance
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If you find something kegel compatible, @Boardnamics seems like he’s cooking something nice.
I think there aren’t many options out there anyway
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I heard Dex is working on some 130mm Thane 
maybe boardnamics? But yea, most gear drive thane builds experience serious small rocks and pebble damage
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