Racing go-karts are fun to race.
I love riding go-karts, which is an open-wheel car.
Once I rode some that looked like bathtubs. 
That's hilarious. Go-karts come in all shapes and forms.
It does make it more fun to try different ones.
Superkarts are supercharged Go-karts that can beat racing cars.
I haven't heard of that. Where can I find some to try out?
Superkart
Superkart is a form of motorsport road racing in which the class is a racing vehicle sized like a kart but with several characteristics more strongly associated with open-wheel racing cars.
The most obvious difference between a Superkart and any other form of kart is that they have full aerodynamic bodykits and can race on car circuits over 1,500 metres in length. The power unit, most often, but not exclusively two stroke 250 cc engines, can be specially designed kart engines or production motorcycle engines with either five or
Go-kart
A go-kart, also written as go-cart (often referred to as simply a kart), is a type of open-wheel car. Go-karts come in all shapes and forms, from motorless models to high-powered racing machines. Some, such as Superkarts, are able to beat racing cars or motorcycles on long circuits.
Gravity racers, usually referred to as Soap Box Derby carts, are the simplest type of go-karts. They are propelled by gravity.