My young cousin folded up the "suspension" fork of a cheap department store bike while doing a modest jump off a ramp at all of 75 lbs., ripe old age of 9. Can't remember which store it came from, but it should be illegal to sell crap like that. Fortunately he got away with skinned knees and elbows, could have been much worse. His parents were well meaning, just didn't realize how bad cheap bikes can be.