I’m honored man, thanks!
More thinking again btw : could you guys post your wheel pulley inner + outer diameters and thickness? What about the motor pinion thickness?
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Me 1st for beta testing 
looool
Here we are !! The VanaLab is back !!!
F*CK YEEESSSS 
make it happened, please! I waaaaaaaaannnt it, sounds crazy (quiet) !!
If we can help in any way, please do not hesitate with my friend 
I’m all in !
(got some mount too if you want, which should be different from Andy’s, if you need more esk8 or MTB LMK 
)
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how would it differ from direct drive?
It is/will be geared (I mean you can use different ratio, if I understood correctly), unlike the direct drive / hubmotor.
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hmm interesting… is it like this video:
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Hahaha Thanks for your enthusiasm, yes I’m on it ! 
I’ll build a first test rig by monday with smaller magnets first to peaufine the movement.
That’s correct !
@Riako yes if you can lend some mounts that’d be great ! I also have @moon onboard helping out 
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Actually same logic but not like this design, I’m going a simpler route. Will be better with pictures, I’ll sketch something tomorrow to post (it’s 1.30a.m I’m in bed).
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that sounds interesting. Tell me if iam wrong but wouldnt you need to produce the same power twice (motor and transmission) in single or 4times in dual to get the power to the wheel? Wouldnt you need something like
1-2 vescs extra and a much bigger battery to get that working? Ok but the BIG advantage is you can frictionless free roll yeahh. I am excited anyways but Iam a bit sceptical for the software/timing also 
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Definitely a cool thing to make, frictionless??? Noiseless is an extra addition, sound is kinda nice though at times. I for sure wanna get one of these for my trampa. 150€ to 250€ range, count me in! Hopefully you can make it more compact than typical gear drives so there is more clearance.
Upgraded gear drive, more efficient, probably just as quiet as a hub motor? No lubrication, probably barely any maintenance. Sounds amazing.
Want to see how it turns out, however you design this it will be cool. Definitely seems like a difficult thing to make though.
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I don’t think, or I don’t really see/imagine the thing right.
I was thinking it is a new type of gear drive (as a belt, chain or gear, but with magnetic transmission _ yes the magnetism must be super strong).
Roughly, something like that (you still got your motor and a motor mount, motor (magnetic) gear, wheel (magnetic) gear too, but the different type of gearing) :
hahahaaa, this is helical magnetic gear drive !
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Sounds pretty interesting, will definitely be following
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Interesting point, I will be checking with different magnet types how to kill the cogging effect which would be the source of drag and / or extra effort but as is I don’t see any reason why it would require anymore watts than a classic gear drive.
What I have in mind is pretty basic 
So VESC timing and prog shouldn’t change a bit from what we’re already using, and it will use different ratios too so torque can be multiplied just like belt & gear drive (I’ll be able to confirm on my own as soon as I make the quick test rig)
Could you please elaborate ?
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Wow thank you everyone for your enthousiasm, I didn’t expect this much interest and I’ll try my best 
Yes that’s what I have in mind ; actually I’m not worried about magnets being strong enough (there are tiny magnets of 9kg / 90Nm of force available and I’d like to actually know how much force a pinion tooth exerts over another pinion tooth when spinning gears ; Another way to play around this would be to redirect the magnetic fields by switching the magnets position)…
Let me grab my notebook 
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INTERESTED in low friction, sign me up!
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As we at it, maybe it makes sense to make that thing enclosed? Like into a gear case from @moon which already fit a lot of trucks.
That would help to not damage the magnets when stones hit the drive.
Also one concern I have.
What you think all that will add up in weight?
1-1.5kg for an all terrain dual drive is good, but over that it get really heavy. That might not be a big problem for street boards, but for the mtb guys who plan to jump etc. light weight always win.
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@Arzamenable Noted!
@Andy87 yup that’s a good suggestion, a case would definitely be a good thing, moon also recommended it.
About weight it is too early to give an accurate answer but I’m actually thinking the heaviest will be the mount (regular material so I suppose aluminum or steel cause it takes the most abuse when riding) and not the magnetic drive itself : neodymium magnets are pretty lightweight.
As example with worst case : let’s call one motor pulley 10 poles and a wheel pulley 18 poles with the same 9kg force magnets (assuming this much force is needed and sufficient). That’s 28 magnets, each magnet weights 21gr
So in total 28x21gr = 588gr worth of magnets.
Rest of structure is classic material, so yea hopefully I can achieve something reasonable 
Edit : Here’s the basic logic in schematics, either horizontal or vertical layout + lined up or asymmetric magnet placements
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Long story short:
The force on one of the drive magnets could easily be 184 lbs / 83.4kg.
suppose we have a 140kv motor at rest at a the bottom of a steep hill. it has a 1cm radius drive gear. the controller is set to 120a motor current limit in BLDC mode.
we get the torque per amp: 60 / (2 * pi * 140kv) = KT = 0.068nm/a
we get the total torque: 120a * 0.068nm/a = 8.185 newton meter
we get the tangential force delivered by one of the magnets in the drive pinion:
A = Motor Torque newton meters = 8.185 newton meter
B = 100cm radius (1 meter radius)
Y = Tangential Force on Magnet
Z = 1cm radius drive gear
Y = (A * B) / Z = newtons
Y = (8.185 * 100) / 1 = 818.5 newtons
818.5 / 4.448 newton/pound = 184lbs
I still think its a good idea but I think you’ll have to arrange the magnets similarly to the video I posted previously which appears to engage all the magnets simultaneously…
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That’s ginormous torque ! Well that’s assuming a 1meter radius pulley so it sure helps building tangential force, I’ll never achieve this much with a tiny pulley but damn, for an e-bike setup this will be gold !
And thank you a lot for the calculations !
Actually I might try both arrangements but in different environments : the setup in your video (or a derivative) would be perfect base for magnetic planetary gearbox… and it wonderfully solves issues I had with my inlines build, with magnets + big bearings I could make a bulletproof and again noiseless planetary geared DD!
no it doesn’t assume a 1 meter pulley… it assumes a 2 cm diameter pinion (the meter comes from the torque in newton meters)
the torque the motor produces is 8.18 newton meters… you would measure a force of 8.18 newtons at the end of a 1 meter lever attached to the center of the motor… but you aren’t measuring at the end of a 1 meter lever, essentially, with a 2 centimeter diameter pinion you are measuring the force at the end of a 1cm lever which multiplies the force as would a lever.
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No way! Ok let me dive again in the formula more slowly.
Edit : Ok, I got it !
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