My nephew is age 8, and weighs about sixty pounds. He fits well on his Giant "Modem G", with 20 inch wheels. The cranks are way too long for his four foot height and little legs, but that does not seem to bother him. The chro-moly steel frame and beefy wheels cause the Modem to weigh at least 30 pounds, which is half his body weight. (That is like me riding a 100 pound bike...yikes).

However, the bikes that weigh a lot less than 30 pounds are either cheap, flimsy models, or mega-expensive models with aluminum frames. The weight does not bother him while riding (and I'm the one that has to pick the bike up and carry it into the house...not him).

What I like about the Modem is that it uses "standard" size tires and tubes that are easy to find, and that it is absolutely "bullet proof". My nephew thinks it is fun to ride at full speed along a loading dock, and fly off the end of the dock and see how far he and the bike can go before landing in the parking lot. His "flying" lessons have given him a bruise or two, but the bike and wheels remain "as good as new".