On the motor tear down, I would like to know a few more things. I am no professional on these modern large scale motors as the only brushless motors over 15kw in power I have dealt with are around 10 years old.
First of all how old was the motor? He said he was on of the first to buy one in Europe. I do believe that the 80kv M40 model is one of their oldest models that hasn’t been redesigned and because of that its not even on their website.
There are some things that I am really concerned about. the main thing being how they balanced the motor. I feel like there should be a better way to do it. On that size of motor bearings could also be a concern but when it was built for large scale drones that use very light weight propellers I am not too concerned.
I would like to point out the price. If you are comparing it to say Hacker, Rotex or Geiger the quality may be lower but the price is also a ton less. You get what you pay for.
MAD components does have some better motors for paramotor use such as the 50kv and 43kv M40 motors. Both of the motors are physically bigger than the 80kv model and can handle a lot more power and torque. Also both of those new motors have bigger bearings.
I have recently ordered one of these bigger MAD M40 motors and it is too late to cancel the order. I will be interested to take it a part and look at it myself and probably post some pictures to the form. I know that the mad M10 motors have performed well on the Open PPG X4 and I believe that the prototype MAD M50 motor has also done well on the SP140, so I will keep my fingers crossed that it will be a better motor that what @ITGlider ended up with.