Minibikes have standard lawnmower gas tanks, and sometimes a fake motorcycle tank on top. We remove the mower and fake tanks, and replace with a real motorcycle tank. It looks better, holds more gas, and is much easier to fill.

Parts:

Tank
https://www.amazon.com/dp/B09VPJH4SD

Cushions
https://www.amazon.com/dp/B08FCFLXB2

U-Bolts
https://www.amazon.com/dp/B09YCZR969