how young is to young?

I think it depends on the child's maturity but also what kind of help you have with you. If the kids are little bitty it helps to have another person there to make sure they don't go runnin into a bay and getting themselves seriously injured. My little guy has been going out on the fourwheeler since about age 4, but he just recently has been allowed to get off and go anywhere near the bay and he turns 6 in August. I think another important factor is how well the child listens. You have to be sure when you say get outta the way or stay back they are willing to do it. As long as you keep the safety of your child as your priority, tons of fun and adventure for kids of all ages can be had.