Yknow a harmonic drive or cycloidal for esk8 would be interesting but I feel like it would be pretty complex to try and integrate in a cheap-ish way into our hobby
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AFAIK are the hubs from inboard were planetary geared, but their construction was not very reliable.
I personally think that its not neccesary for hub motors being planetary geared, but im no expert.
Hub motors just have to get smaller(more urethane) and more powerful in the future if that is possible.
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have to chime in and correct my prvious post…it was stary not inboard.
hahahaha silly me hahahahah
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happens to me all the time hahaha
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yeah, the big benefit is you are able to use really big motors on standard sized trucks and they look so bad ass 
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Still completely incorrect. Adjusting motor kV has the same effect as gearing. You can also offset kV by extending the stator as hummie has done.
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Agree to disagree 
True but I’d like to see you do that on the fly when I’m just swapping some pulley and belts in 10 minutes 
plus I would also imagine that heat and stator saturation are much more likely in hub configuration compared to belts and hence would take more torque away from hubs.
There are also limitations to what you can do with winding configuration and usually that gets into the more expensive territory compared to belts and pulley
I have Carvon direct drive 4x4, Hummie V4 2WD and a 3D servisas Gear drive 2.6 ratio with 6384 190kv motors. The Hummies have crazy high torque, so much that I had to turn down the amps on the unity to compensate…
Also, who changes gears and belts on the fly for different performance?
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Same wheels and everything else?
True most people don’t really do that, it’s set and done and you tend to leave it as is. But the option is there should you decide to swap batteries or wheels. With hubs, you can’t really do either without taking a hit in torque (actually not even sure you can easily switch wheel diameters with hubs. Maybe DD?)
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This guy made a Harmonic one for ebikes, there is a whole development thread
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I have yet to see a cycloid or harmonic drive with a gearing lower than 10:1. Seems better suited to a bike transmission but I’m all for innovation.
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I wonder where the line is drawn where complexity causes more problems than it solves. Does down scaling affect the durability of the design to the point where it’s better to keep it simple?
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Yeah, it’s not practical, for a low reduction you need low teeth count, and that isn’t possible, better going with planetary
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WOW that is awesome!! I just checked out their website and it looks super cool. Makes sense for a bike too to get that much power out of a smaller motor. Smaller motor means more efficiency and more battery life!
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These Astro flight motors are crazy, I want to see someone using them on boards one day, unfortunately also crazy expensive
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i would think vintage shit like that can be bought for cheap on rcgroups today. i have an astro bob inrunner with a 4.4:1 maxon planetary geardrive somewhere in one of these rc sailplanes. yes i have thought many times how it might make a great single belt drive for a skateboard (8mm output shaft is ideal for our application), but honestly i’ve always thought those maxons wouldn’t gracefully handle the kind of sudden jerks and off-axis forces that our esk8 motors have to put up with. honestly today’s outrunners are priced so low we can treat them as consumables
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Just looked at the price holy crap lol
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We build cycloid gearbox for some customer project. It have large reduction ratio for high torque and low speed application. Is complicate for manufacture small size like we did.
I think for skateboard spur gear is OK.
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@longhairedboy @linsus they’re called ekewill. I’ve ridden the 2wd model and my God is the planetary hub loud
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I need to look into planetary hubs
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