i don't know why it would need to be registered and have a plate...unless you're on the road or maybe at a state park with ATV trails. If you're riding around on private property i wouldn't think they could have anything to say about it. but <span class="FTHighlightFont">i didn't read the laws.</span ft> good luck

 

Here's a link to the PA ATV laws I was referring to.
The land they are riding on isn't owned by them, someone's farmland they use, but do not have written permission. Also, if he wants to go to other approved trails, it's required.

PA ATV laws