Hi there, I've been trying to find out what these are called, but to no avail.

Do they have a specific name to them?

Thanks

Bricklink calls them Ninjago Spinner Crowns. The grey with flames is specifically called Ring 4 x 4 with 2 x 2 Hole and 4 Arrow Ends with Yellow and Red Flames Pattern. You can find the listing at http://www.bricklink.com/catalogItem.asp?P=98341pb06. Search "spinner crown" to see all of them.

Thank you