Lemme get this straight...
You help you mom pay rent (Something no kid should do), but she wont allow you to buy a truck with your own money? LOL, no offense, but id tell her to goto hell.
She makes sense. If he doesn't have his licence, he will still have to register ( And insure in my state ) and he can't even drive it! So there isn't really a point. So saving up more, can turn into better truck/better quad.
Hang in there, you don't have a quad, mines almost always broken! I know how you feel, i gotta pay for all my quad sh*t, and my own car, insurance, and gas.