Another is the CPSC not allowing dirtbikes or quads to be sold if intended user is less than 13 years old. Lead is poisonous and used in the brake cables and engine parts. If ingested it could cause cancer. Don't know about you, but I have my daughter wash her dirtbike with tongue, it just works better.
On top of that, when the kids touch these bikes they wear protection from head to toe and pretty much never touch the bike when they aren't geared up. Who do you think gets stuck washing the thing all the time?