Argentina to seattle
 

I realize im doing the pan america road backwards. But this is how im going to get home from traveling the past few years. I want to start in july but probably wait till august because of the weather. Does anyone know how i can buy a bike there?

No one answered you? Wow. Buy a US registered bike from a traveler who finished his r her trip. Get it registered in your name and just go.

Well, of course it's more complicated than that. For example, you can't do that in many states, and even where it's possible you (mostly) have to show up in person, demonstrate proof of residency, or jump through other hoops.

OP, if you're still around: Probably the reason no one answered is that your question is asked at least once a week here, in one form or another. Plus you don't give any indication whether you've done a bit of research on your own, which can give you a big leg up on understanding what's involved.

I'd suggest doing a site search and spending some time reading up on the subject. That'll help you formulate more specific questions, and you'll attract more useful answers.

Hope that's helpful.

Mark