One point important mentioning though is that once you put a motor on the bike you kind of have to use it all the time, because 1/ you lose the front derailleur, 2/ motor + battery weight around 6-8 kg, and 3/ the engine is always engaged.
It's possible to use the bike with zero assistance, on flat ground, if you need it (for example if the battery dies), but it's not something you want to do all the time.
So, it's not really a sport anymore. Yet it's extremely pleasant.
Also: you can buy Bafang motors on Aliexpress or Alibaba; I find sellers on Alibaba much more professional, and most will agree to sell just one item.
