I think that is why he thinks torque must be the problem here. usually you have belt drive systems where the wheel sits on bearings and the axle only has to withstand gravity. With a hub motor the stator core actually needs to stay in place. So the axle does need to withstand that additional torque exerted by the motor. Personally however I doubt that this indeed has anything to do with torque and believe this is just like @3sly and you said.
In the end itās probably a mix of factors that led to the failure.
We are also not 100% sure which component took the torsional force? Was it purely the axle because the motor was epoxied in? Maybe the motor not even touching the hanger? Difficult to tell by the pictures, enven though they were posted multiple times. Then we need a design where the torsional forces are taken by the hanger not purely by the axle.
this is an image of a drive shaft that snapped due to fatigue (not torsion! - this one is due to torsion)
I have to admit: does look similar to the images we have seen a thousand times now.
I agree - something like the DIY clamp with some screws you can mount the motor to should already help for both torsion and leverage/bending (and should fix this stupid epoxy usage - although props to the epoxy if this was actually torsional 
).
because this image comes from a website of a professional material inspector/scientist and is marked as such. Please just look into fatigue fractures http://lmgtfy.com/?q=fatigue+fracture and you will find images like this: http://images.slideplayer.com/14/4225228/slides/slide_8.jpg almost perfectly describing what we see in your images. In fact after looking into this a little I am now convinced that torsion had in fact nothing to do with this. It were surface defects (probably caused by dremel) and a resulting fatigue fracture (especially with the sort of vibrations we get on skateboard wheels). Does that sound right @3sly?
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@devin This has to stop manā¦ Iām very close to closing this thread its just filling with useless crap/spam now.
Its very simple. No matter the root cause of failure. Hummie needs to rework his design and somehow make it more robust by improving the mounting mechanism design / motor concept. Otherwise it will remain unreliable and unsafe.
Standard skate trucks probably wonāt be relaible long term, but if you insist on using them my advice is to completely isolate the axle from all loads.
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you need some Dayquil for that cough of yours.
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I just learned about crack propagation in SAPOEM. 
Got the question wrong on the final however 
.Still got what I needed for my A
The banhammer is going to come down hard.
How much wider is the single Hummie Hub-Motor compared to the CARVON āHub-Motorā?
As far as I know there werenāt any issues with the CARVONs, maybe Hummie could mount them the same way and give it another shot.
Iāll mount the other one i have and see. but I will cut back 8mm of the hanger because it makes it equidistant and Iāll be sure not to touch the axle with the dremel this time.
Iāve been fishing for thoughts and @mmaner wrote to me that maybe there should be a gap between the motor and mount. Counter intuitive maybe but it would give room for flexing of the steel is the theory. Maybe Iāll add a tiny hard rubber washer in between.
Iām just guessing, as I havenāt seen the manner of construction. It makes sense that spreading the stress across a longer surface should lessen the possibility of stress cracks/fractures in the substrate.