Here are my proposals for your logo. I want to do give it a look that would work also as you further your career. I have a few client/friends that started their racing career in karting and have since moved into NASCAR, so I understand the importance of branding oneself. I tried to keep the logo very much in a racing theme, but did not specifically stress the karting aspect. Howevr if you feel that for the time being, you might like to see more of an association to karting, just let me know. Please have a look of my portfolio and let me know if there is something else in my style of work that you may like to see. Feel free to request any changes, be it color, fonts... you name it.