BTW thank you for posting this. Excellent read. I’ve often wondered what the weird gears inside slot cars were called. Now i know they’re crowns.
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Thank you for giving me a place to post this 
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Weak torque relative to belt drives. Hubs lock you into a set gearing. With belt drives, you can gear torque as needed. But I mean you’re right, there are plenty of parameters you can adjust in the comparison to favor one over the over. I just haven’t seen a lot of well made hubs just yet.
Yeah ride comfort leaves much to be desired but that’s why I run DDs instead 
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For the torque and efficiency ofc. DD ruins the illusion of no motors
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Planetary direct drive is super interesting. Frees up more motor kvs because it allows for 100:1 - 3:1 gearing ratios. If you made a sleek enclosed mounting shell for it, you would kill it.
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Would adding gear on top of hubs make the heat dissipation worse though?
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Well hub motor itself is kind of terrible at dissipation already. Don’t think adding the extra space for gears will make it worse but the cause gearing will help with current draw. Less current=less heat. Pf=R*I^2
Found this gem: https://www.electric-skateboard.builders/t/first-build-dual-hub-motor-internal-planetary-gearbox-4260-300kv-vesc/20111/162
Probably the best attempt I saw, even tho it didnt quite work properly in the end.
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@Venom121212
awesome find.
With regards of gears vs belts you guys know where I stand and now that ESC tech has gone up a notch gears make more sense.
Combining a 4:1 gear setup with a 180Kv to 190Kv and a 72V battery pack, will perform perfectly in 95% of all situations, the rest 5% will be @MoeStooge territory 
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Would it? Thats like 65mph top speed with 8" tyres
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he rides 6", 6.5" tires
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my bad thought this was another thread
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Oh i never heard of that. Only saw a build thread/concept for a personal board. Just scrolled up… the link you posted was it! Thats the one i remember.
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A man of culture I see 
I have extra “free” time with the virus, hopefully I can find time to work on that. Should not be much expensive to make a test rig. Hardest part is to have enough magnet power to keep torque without slippage.
Just another variant of the magnetic drive already. Challenge accepted.
Edit : I wonder if using big ass magnets at core and slimmer magnets to multiply pole counts could work, in addition with slim iron layers in between.
@Venom121212 Thanks for the inspirations, damn these two last drive trains are epic AF!
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Yes indeed
My boards are 8 inch.
it will be super fast and also have a robust low end torque.
The power delivery can be setup in the ESC by having custom modes for every occasion.
On the top speed better not to try it without stabilizers and proper safety gear.
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i stand corrected
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Planetary gears were actually released before hub motors in 2015 with stary board, whereas inboard did hubs a little bit later on indiegogo iirc.
“Volans” or whatever the DIYeboard guy’s name is also had a functional planetary system as early as 2015, with a full transmission setup like Baja.
(Diyeboard is still a crappy seller though)
The “ecomobil” board recently came from china as a v2 to the original china baja clone, with planetary gears. Here’s a video
Its $1500 with a 12Ah battery and poor quality ying li ESC
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How much power are you pushing to have such a high top speed AND reasonable torque?
Madness.
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Thank you kind sir,
I was thinking about this, the same stuff used in robots, as i understand there are no magnets, but just precision maschines fancy metals.
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Those spiral bevel gears! 
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