How to make 5 hp brigg gokart motor go faster?

Answer 1

increasing the size of the sproket will increase top speed, but slow down on take off speed on either sproket.

So, increasing the size of the sprockets will increase top spped, but will take it longer to get up to speed.

This is why we have transmissions, it is a sequence of different size gears(sprockets) to manipulate the speeds.

Answer 2

run it on alcohol