Then you'll get an idea of what James "Bubba" Stewart is to Supercross and Motocross racing.

In just his fifth year of riding professionally, the 20-year-old has won four championships -- two in Supercross (indoor, man-made tracks) and two in Motocross (outdoor, natural tracks). He holds the record for the most career professional victories (47) in AMA Supercross Lites and Motocross Lites (smaller motors and half the number of races).

He really put in more of an effort than most, and he's really changed how a lot of people ride now," said crew chief Jeremy Albrecht, noting that Stewart has perfected the art of passing other riders in the air by turning his bike sideways. "He studies. He works on that all the time at home. He rides probably more than any other rider ever has."

It is Stewart's study habits that may land him in a stock car one day.

"Actually I have an interest in NASCAR for sure," Stewart said. "People look at it differently, but I consider what we're doing, with all the different people in the industry and all the guys racing, I think that's NASCAR to us. It's the top level."

NASCAR -- or even racing in any type of cars -- isn't his goal just yet. He still has a lot of riding to do on a motorcycle. This is just his second full season of racing in the 250 class after dominating the 125s. Plus, he wants to make up for last year.  More at NASCAR.com