That’s what inrunners are for, you’ll never see it on an outrunner
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Thats right if you’re at the point where you can gear down 20k rpm then inrunners are the go.
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I just added one set of 125kv. Order is locked in now so thats the only set of 125kv motors we’ll have for a few months lol
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Hahahahaha this is the beauty of forums full of hobbyists, nice one
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any chance you can give us some benchmarks on the motors?
Theres a utility in vesctool to do an approximate benchmark nowdays 
Shouldn’t take that many minutes
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Thanks! Just put in a pre order through your site, it’s just for one motor though (one wheel), hope that’s ok.
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Thanks! Do you perhaps have another friend also building a onewheel? 
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What kind of benchmark? There doesn’t seem to be a standardised test for power. We have a dyno test of an older version without cooling and weaker magnets.
245kv @ 50V - 6318W in and 4981W output at the shaft, 4.25Nm at 11,187 RPM.
But it doesn’t mean you’ll be able to send over 120 battery amps into each motor without overheating
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We can only hope my experiment with belt driven one wheels is a success, cultivating a similar DIY scene for one wheels and demand for low KV motors .
It’s being built up with an APS 80100 50kv motor, once that works (
) I’ll get some stats and swap with the Radium. Will be I interesting to see how it goes compared to something almost double it’s weight.
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This but plotted on a graph over RPMs.
Things like efficiency and idle current draw is intresting too.
example:
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interesting…i was thinking about 173kv for my 12s board, but now i’m considering 205kv
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Oh it did, as I mentioned I’m comparing non preorder prices, which should be the point of comparison unless you plan on having it at the preorder price permanently.
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Huh, I only just noticed the currency selector. I didn’t think to look on the bottom left of the screen for one. Never mind me then!
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Yesss good. It pains me when I see people running 170kv motors on 10S. I’m like duuude you’re missing maybe 35% more power than if you just ran whats typically max recommended kv and voltage (usually 190kv / 12S)
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Have you done any tests on the advantages of N38EH mangets vs N42SH? I order my motors with the N38EH magnet due to its higher temp tolerance, but I am not sure if there is much advantage since our motors don’t ever really heat up to those levels.
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Maybe they don’t but at least that means you could ignore the normal 100C vesc temp limit and just slam your motors to no end without worry
Default motor temp cutoff is like 80 I think, hottest I’ve ever gotten my FS is 74
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Yes I agree. I change my motor temp cut offs to start at 120c and end at 150. The hottest I ever got any motor was some TB63100s on 18s, got them to 134c and they still seem to be working fine today. My reachers have never heated up past 80c. Even the 150c rating is overkill, but I think if you were to actually get the motors hot hot, into the 100c and higher maybe at that point you would see the advantage of the higher grade magnet as it would do a better job at retaining its magnetic properties.
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Damn, those look good, next build, if there ever will be one 
Ps, @Tony_Stark could you change default currency for iceland to usd, or isk if thats possible
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This is way too hot. Even though the magnets and stator windings may be able to handle such temperatures, the epoxy holding the magnets in place would likely degrade. The bearings may also not be happy at these temperatures. I’m not sure what temp the grease is rated to, but since the bearings generate their own heat, if the stator is already at 100C, the bearings could be another 30 degrees or more ontop of that. So I’m not surprised Reacher says dont exceed 100C. I would set my cutoff to 90 start and 100 end, regardless of magnet grade. The temperature rating of the magnets is also more complicated than it appears. The temperature rating is only one part of the equation, the other part being the field strength acting on the magnet. If you take a 180C rated magnet and supply a sufficient magnetic field, you could begin to permanently demagnetise it at even 100C. So higher temp ratings are always better, but cost can increase quite considerably with the temp rating. The magnets are about 30% of the overall cost of these motors.
We’ve got 1 set of motors coming with some different magnets to test out on this batch. With the hope of achieving even higher torque without messing up FOC performance.
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