[closed] GPX and Relations

I'm not sure why my question was ignored here. Maybe I asked it wrong.

I need a GPX file of a route I would like to ride on my motorcycle, which I use MotionX for. I want a GPS trace of a specific road, and only that road, so I can import it into the app.

I noticed that the "relation" of the Blue Ridge Parkway:

https://www.openstreetmap.org/browse/relation/55450

when I click "view relation on a larger map" I get a nice blue line, which I would like to export as a GPX. I don't care HOW I get the GPX, I just want the same thing as a GPX. How do I do this?