When I change my oil, I let the bike drain for 10 minutes or so on the sidestand, with the dipstick out, oil plug out, and filter off. Then, I get on it, and rock it sideways back and forth -- as far over each way as I'm comfortable holding it -- three or four times each way. More oil definitely comes out, not a huge amount, but noticeable.
I split my oil changes between 9 quarts, i.e., 4 and a half each time. (I use the see-through gradations on the quart container for the half-quart.) And then, with the bike upright (in a wheel chock), I run it for a minute or two, wait the specificed 3 - 5 minutes, and check the dipstick.
I mention all this because the level's always then right at the top of the full mark. So my point is that -- at least for my oil changes -- if I didn't rock the bike sideways -- putting 4.5 quarts in would result in the oil's being higher than the full mark... and so maybe overflow would come into play.
Incidentally, I've never had any overflow problems, at least that I'm aware of. 32K miles on my '12 XCT.
2012 XCT (SOLD)
: HeliBars; Centramatics; PC-V; Lloydz air filter; 11" Madstad; Rivco LED mirrors; Doran TPMS; Stebel horn; Motolights; CustomLED trunk flasher; KewlHeel shifter; CycleOps trunk rack; BeadRider seat; Vibranator bar ends; Passenger grab handles; Powerlet outlets; Handlebar RAM mount; RicZ laydown plate; Brukus SaddlebagSecure; 14" flexible antenna; RAM cupholder on trunk; shock Schrader valve relocation.