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I am not sure how big your son is but if it were me. I would put him on a crf150f instead of a 100. It will give him at least another year on that bike compared to the 100. My boy is on the 85yz and he is only 13. Just the other day he threw his leg over my RM250 and kick started it like he owned it. I was Now he says he is ready for a big bike. I said next year my boy...next year. The grow fast. One day they are 5 ft nothing the next day they are standing next to you looking over your head. Good luck onthe search.
I am not sure how big your son is but if it were me. I would put him on a crf150f instead of a 100. It will give him at least another year on that bike compared to the 100. My boy is on the 85yz and he is only 13. Just the other day he threw his leg over my RM250 and kick started it like he owned it. I was Now he says he is ready for a big bike. I said next year my boy...next year. The grow fast. One day they are 5 ft nothing the next day they are standing next to you looking over your head. Good luck onthe search.