I want to build an eBike for myself. I've read a lot on the subject of converting Bikes to eBikes and I think the best approach would be to build a so called friction drive, wherein a small RC BLDC motor (so called outrunner motor like this) directly turns the real wheel by friction with tyre.
Problem is, RC BLDC motors need ESC (Electronic Speed Controller) to run and as RC BLDC motors are built for applications like RC Drones, Boats, Cars etc. their ESCs burn out (probably due to high amp draw by small motors under high load) and high amp rated ESCs are costly. They burn out too, I've read. There's also open sources VESC, which is equally costly, and I can't build it.
So I came across this cheap "sinewave" BLDC motor controller, which claims to control Brushless "Sensored" Motor. My question is, can I use this controller instead of ESC to run RC motor linked above? If not, why not? I understand that RC motor I'm talking about seems to be 2 kW and the controller is going to provide just 250 W power to the motor, but that wouldn't hurt the motor, right? This controller is best option because it is specifically made for eBikes and has many other features/sensors for eBike purpose. Also supports Cheap Lead Acid batteries.
If above controller isn't advisable, my Plan B is using this ESC, which is cheap but unbranded. Problem with burning ESC is high amp draw when eBike tries to pick up speed from stand-still only using motor. Can I use this ESC safely with the same RC motor referred above if I use the motor only when bike is already in motion?
Plan C is to use this RC Motor/Controller combination (which seems made for each other, instead of matching an ESC with a Motor sourced from different places) and run it carefully (only while eBike is in motion) like Plan B. It's rated at just 820 W, which seems plenty for an eBike.
Overall purpose is to make my bicycle electric assisted by spending as little money as I can. US$ 100 Motor and US$ 100 ESC, plus Battery cost are too much. Also, as you can see, I'm looking for a plug and play approach, don't have much know-how to modify electronics myself.
If you think above setups aren't good thinking on my part, do suggest other affordable ways. Hub-drives are even more costlier, so friction drive seems best option to me. It's simple and elegant.