Not 100% sure... but I think I've read it on this forum somewhere. I believe it refers to the steering head bearing test/adjustment. In my manual, they call it the swing-by test.
You lift/support the front of the bike so that the front wheel just clears floor/ground. Turn the handlebars completely to left lock and release. The handlebars should now swing to the right, back to the left, back toward the right and finally stop at or near center. My manual shows the pattern and how many swings are too tight/too loose and the adjustment needed
I could be wrong about the reference to the "fall away test", so if anyone else could verify... I simply could not find the thread to prove/disprove it.
2003 Anniversary Edition. 95" stage II, lowered 1" front & 1.5" rear with Progressive mono's & 444's, King Tour Pak w/quick detach mount, 10" mini apes & 11" Madstad.