"Racer Knights of Falconus" and "Racer Knights" are registered trademarks of Arthaus, from a time when it was an imprint of White Wolf Games, which is itself currently an imprint of CCP Games, who (depending on how accurate the Wikipedia article is) merged with White Wolf mainly for the purpose of being able to make an MMORPG with the World of Darkness property, and may not have any interest in Arthaus or the Racer Knights material.
What does all that mean? Honestly, I have no clue. But Racer Knights of Falconus doesn't belong to me, and my game isn't in any way a product of or endorsed by Arthaus, White Wolf, CCP Games, or anybody else but me, m'kay?
That said, the pieces that do belong to me are released under the Creative Commons Attribution 3.0 license. Which (summarizing the summary) means that you can do pretty much anything you want with this stuff so long as you tell people where you got it. And that only applies to the stuff I did, which is everything except the logo, which was adapted from the SOM Phoenix piece placed in the public domain by Mike B; and the pieces of original art done by Chris Rywalt (none of which are up yet). I'll attempt to make sure it's clear which art was done by who, but if in doubt, if the art is good, it was probably not done by me. Further, according to The US Copyright Office, game mechanics aren't subject to copyright protection. So you could make a game that works exactly like mine, and I don't get to say anything about it anyway.