How fast can a 5HP Go-Kart go in MPH?

speed is determined by the size of the gear on the motor shaft [small] and axel sprocket [large] 14 in wheels are huge,,, top speed could b in the 30 to 40 mph range but faster the top speed the slower the acceleration

http://www.diygokarts.com/speed-calculator.html

go to this website
enter size of tire measure all the way around the tire, best way is to mark the tire and a spot on the ground roll the tire until the spot on the tire is back to the ground and mark the ground again, then measure point a and b on the ground,
if it is a 5hp it is going to be at about 3600rpm it is industry standard. then measure the teeth on axle then teeth on clutch. it will be a close measurement of your speed. your weight wont have much affect on your top speed just on your acceleration, but if you want top speed your going to give up that anyways, go carts are a give and take on top speed and acceleration, it is best to find a medium, about 35 mph will still give you good take off and that is pretty fast for a cart

can i mount the rear axle of my 5hp go kart on normal round bearings.. with 13inch wheels

help

lm making a go kart, the wheels are 10'', and it ways about 150 lb. i want its top speed to be 20 mph. what kind of engine should i buy?