I have 2 boys ages 9 & 4 and they are already into karts. We have 3 miniature model t karts rangeing from a 1959 heart shaped seat to a early to mid 80s coca cola kart along with a Yerf Dog suspension kart & a Kasea 150. I am working on my wife to let them have a mini bike or 2. I have learned quite a bit reading the forum here & hope to learn a lot more.:thumbsup: