My son turned 8 about 8 months ago. Recently we bought him a Felt Z24. Had to change out the bars for some with a very short reach, and narrower. He also insisted on going clipless, so he got some BMX shoes that fit and take SPD's. He's happy as a clam. Done a few 34 mile rides with me at his pace (actually, I rode with him).
He had less trouble learning to clip in and out than many adults I know.
He loves the bike and rides it often. But he's never alone. Either my wife or I ride with him. If he wants to go knock about with his pals, he takes his BMX bike. That way I don't have to worry about it vanishing.
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