There's no real age limit on when you can ride a motorbike...my kids were riding motorcycles at 7yrs old. Mostly depends on your skill level and what they call "Rider Fit Test". You can google what that is for more information. Hope that answers your question and helps.
It is all skill level of your child and how many tantrums you are willing to deal with as a parent. My son started riding a strider (balance bike) at 8 months, then a Oset electric motorcycle at 2.5 years, then a KTM mini 50cc dirt bike at 3.5 years. I think AMA racing rules has a minimum age of 4 but i signed him up for a race when he was 3 and nobody said anything. I was able to buy all his bikes at MotoSport Hillsboro... now If you are talking about riding on the street you would need to be legal age of 16 to get a motorcycle endorsement
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