>>1599142OP you are deluded and wasting your time. E mountain bikes and shimano motors are already perfected and available off the shelf. They are vastly more capable than what they appear when you inhibit the regulatory 25kmh/r motor cut off. (easy 50/km/h) plus the geometry and suspension are amazingly well tuned.
You dont need to build one you dont need carbon anything, you dont even need a thousand watts, my "250watt" motor has more torque than my friends 1000watt chink hubmotor and thats whats important. If you want range get a second battery. Just get the cheapest merida e-one sixty you can find, a motor tuning kit and just ride.
These are perfection and are under the radar. DIY is cringe and attracts coppers. You have been warned.