How tall do you have to be

My son is 49 inches and he was good to go

Don't believe there is a height rule, just age. The pedals are adjustable. They have smaller less power karts for kids, can run adult karts if they can beat a certain time.

4 feet you should be good

Not sure on height. 7 years old minimum.

They have Adult track and Junior track, so I don't think height is a big deal.

Any height I believe, I'm 6 ft and sit perfectly. Some co-workers i go with are approx 5'5 and kill the track! Unless you are under 5 feet check with them but you should be good !