I know these look small and scary but its fine. I drive A 250 Winged Outlaw Kart I love racing these things they are so much fun. You can start driving when you are six it used to be five but it was just to dangerous. There are age groups but it depends where you live and what the rules are for the tracks. The main groups 5-8 are pee-wee, 9-12 are Interrmediate karts, !3-16 are the 125/250 class, 16-up are the 500 class I have raced with 40 and 50 year old men before so there isn't really an age group. You just cant be like 10-12 and be in a 500 class that is just too dangerous and you wont do so well normally the kids and adults in that class worked their way to that spot so they have a lot of experience. So just use common sense and just go race and have fun.