Yup, now they work.
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Bump, need some more data 
I think gearing it for higher kv motors are the way to go. From 190kv and up as the higher the kv, the more power the motors can handle. Others can further elaborate.
So you want to design something very much like @ janux enclosed belt drive?
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I don’t think motors over 190kv have a real standing for mtbs. Not enough torque.
I think 1:5 ratio is a sweet spot for 2wd, speed freaks can go for 190kv (or higher if you hate torque) and the torque monsters can opt for lower kv motors.
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I read quite the contrary, that higher kv can handle more A which in turn is more torque. I don’t understand the technical side of this but it what I have understood. Let me try and find the thread with that info
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@glyphiks like what is said in this topic
🔩 1:7 belt drive for mountainboard with badass torque
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Thats an interesting read. But they are talking about pretty high ratios for 190kv and above.
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@PixelatedPolyeurthan I’m also thinking to gear the standard setup for the higher kv’s (170 - 190 kv) as this is more common and gives more power. Its similar to the janux drives just for mountainboard trucks. Gonna play with the gearing a bit to see what gives the best form factor, since I want the drive to be compact.
I agree with @glyphiks, the higher gearing would give plenty of speed at 190 kv. Plus if more speed or torque is needed pulleys can always be swapped in a larger housing.
The drive by @Marsl187 looks very interesting, would improve ground clearance and provide a lot of torque, this would be very suitable for the mountainboarders in hilly area’s. 
I am aiming to make the drive a hybrid so it can also be used for speedier builds. Additionally I aim making it as low profile as possible especially in width to hopefully allow 6396 motors. A 6396 190 kv motor would provide crazy torque and still enough speed.
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1:5 @ 170kV is good, wouldn’t go higher in kV for a mtb. Street/AT cruiser can go 190kV and down to 1:4.4 maybe. Below it would be too less torque for me, but that’s just my opinion. Kaly boards run 1:4 at 190kV if I’m not totally wrong and people are fine with it too. If you don’t run bindings too much torque isn’t good as well. So it really depends what people want to achieve with there setup.
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Thanks for the feedback 
yeah it depends on personal preference. I will use these for a street setup, hopefully with 6396 motors. But I love torque so will probably choose towards 1:5 
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A year and a half ago I thought 1:4 is totally enough with 170kV motors. My opinion changed over the last summer. I‘m riding 1:4.89 at 170kV and looking now for a gear drive that can give me even higher gearing 
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The good thing on a belt drive is that you can cover a good range of gearing options.
Setting up the max gearing at 1:5 still gives people the option to gear down easy if they don’t need the torque.
Wouldn’t go smaller than 14t on the pinion thou. So maybe 70/14 equals 5/1 and 70/18 equals 3.89/1 for the people who just need speed.
Downside on the high torque belt drive is definitely the clearance with 8“ and it’s definitely nothing for people who want to go with 6-7“ wheels.
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First concept renders (configured for trampa hanger). 15T pinion, 72T slave pulley, still looking into the idler setup (bearing sizes, mounting) and fasteners. The drive can also be used without an idler.
At the moment most of the design constraints are related to manufacturing, I dont have a cnc yet and I will have to go through a significant learning curve before being able to cnc complicated parts.
Next up parts will be optimised for 3D printing, after printing i’ll check the fit/dimensions and maybe mount the drive and do some rolling tests/low speed riding.
Need to source some HTD5M belts between 440 and 470 mm, If you are reading this and got any left over let me know.
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This looks very similar to the Trampa enclosed belt drive.
It is a solid solution but it has very high drag with the idler and I feel this will be the same.
So as someone that had an enclosed belt drive and has moved on to gear drive my opinion is that they are not worth the effort.
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Why so less enclosed chain drives out there? 
The french guys have some nice options there and drag should be less than belt + idlers.
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I think the case would make for not enough clearance on an enclosed chain drive but I could be wrong.
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Depends on the chain size. With 06b and 42teeth it’s already a very close call.
Case around wouldn’t help there yes.
Buuut 40t is good and why not double stage? 
Options are there
Don’t want to say a gear wouldn’t be more easy/light and cheap
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Thanks for your opinion!
It is indeed similar. However, I aim to use this one on both trampa spring and MBS matrix II trucks, plus integrate a TPU seal along the cover to provide a better sealed drive.
Do you mean drag as in less efficient? I’ve used the 2017 trampa pro belt drive with idler and I got a lower wh/km than my current geardrive, a friend also reported his geardrive was less efficient than his belt setup, so in case of efficiency a belt drive doesnt have to be lesser to a geardrive. But imo the differences are not significant enough to choose the one over the other.
A geardrive is too complex and expensive for me to make myself, so I set out to make a belt drive to gain experience with CNCing. This project is more to develop myself and If there is no interest I will not do a run, Ill just use them for personal builds
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@Andy87 interesting idea, but I was also thinking about what @taz mentioned, the teeth are quite big resulting in larger wheel gears and therefore even less clearance. But might be something to look into because the motor gear can be significantly smaller aswell right?
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My experience has been the exact opposite. In any case it is your project and not everyone is the same so go for it.
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