Bought this for 100$ off marketplace lol

[u/HOODRICH8461]

Just picked up this mini E bike for 100$ (Monster Moto E250) its made for kids but is the same size as a 50cc pocket bike! It comes with a 24v battery and a 250 watt DC motor stock. The frame is solid it also comes with disc brakes. However it is very slow about 15km top speed with me on it (185lbs 6ft tall) and runs for about 20 minutes until the battery is fully dead.

Does anyone have any recommendations for a faster motor, bigger battery and better controller. My budget is around 400$-500$ max! Id like to hopefully double maybe even triple the speed of what it is currently!

If anyone has any ideas or has done something similar and could offer advice it would be greatly appreciated, thank you!