If they can reach the pegs, they are old enough to ride IMO. Training them and mentoring them to "do as I do", quickly builds their trust in my riding skills. If I did not trust my riding skills, I wouldn't even entertain the thought of passengering anyone.
My 9 year old LOVES to ride. Lots of "wows" when I took her through downtown Nashville during off peak hours. The buildings towering above, the people walking around, smells of restaurants, and being in the open air is pretty spectacular. She also likes to ride in a group. The only place that I have not taken her is on the freeway.
My four year old cries when her sissy gets to ride and she doesn't. There are several more inches in the height department before she qualifies.
I tend to focus on my shifting and braking to keep everything at peak smoothness whenever I have a passenger (size and age doesn't really matter). I want them to enjoy it, and want them to look forward to riding (with me) again.
=ike=
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