🔩 1:7 belt drive for mountainboard with badass torque

Basically the box is a plate of POM with many inserts. The rest are 3d printed parts in pla carbon and wood filament. I also implemented the hearo logo in the lid.




The enclosure looks fantastic! Great job :ok_hand:


Because its nicer to have more ground clearance than just the height of the sidewall, especially on a mountainboard. 72t HTD 5M pulleys are already the same diameter as the hub. On the motor pulley end, 11t pulleys are already small enough to need an idler under most circumstances. I really like the idea of a compact 2-stage belt drive… Still vastly cheaper than gear drive. I’d like to see the idler for the motor-to-intermediate pulley eliminated, in favor of allowing some motor movement. (Idlers are only needed if it’s inconvenient to move something else to tension the belt, or if not enough teeth are engaged on the smaller pulley… With 2-stage reduction, a 15t or larger motor pulley, there’s zero need for the second idler bearing stack… Unless your motor is so large it might run afoul of the cross braces.)

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But the low kv has more torque per amp and ultimately it ends up same loss to torque ratio regardless of kv

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the higher gear reduction means the higher kv motor puts out less motor torque for the same wheel torque so less heat til you start looking at iron loss…


Whoa that enclosure is fuckin sweet man!


@Creavenger @DANGItsVictor thank you! :innocent:

Battery is mostly done. Assembled the belt drive today. Looks promising. Got some good ideas already for a v2 already. But first things first. Need to test this one first :sweat_smile: Assembly takes quite long and can be a pain in the ass…
Can already tell that there are way to many bolts in the main case :sweat_smile:

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Can’t watch the video above but the enclosure looks damn nice :ok_hand:

Why don’t you switch to 9" wheels?
Way less clearance problems and still plenty torque with 1:7.

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Took a screenshot of the video for people to see:

Looks siiiiiick! :smiley:


Fuck this is the coolest thing ever


I haven‘t ridden a mountainboard for 1.5 years now… so first getting back to that.
9“ is definetly nice and was also a reason for this drive. Would just need a different adapter plate and the drive is good to go. We will see. I seen that trampa has some cheaper 9“ rims now, which make it a bit more interesting :grimacing:

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Can’t wait to see this thing in action! I assume the eggplant shape is just another subtle way to make us all more insecure and jealous of these drives? :rofl:

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I thought this is just some theoretical thing you would be interested in. Seeing it as a physical object is just inspiring AF to get some of my ideas done.


I know it’s been a while, but curious how this turned out for ya @Marsl187

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