My comment about raw fuel was directed towards the aircut valves on carb 1 & 4, not the reed valves...totally different animal. The aircut valves enrich a lean condition during decel.
My 86 keys were marked GTR also, and it was a Cali bike, I don't know if they all were marked like that. My 88 ones were marked Kawasaki.
to add to what steve related to, I'm also running 36mm Ninja carbs (without aircut valves) on COGZilla, with the reeds still in place, and a set of SuperTrapp Ninja mufflers (zero restriction, and loud), and that bike is just radically loud and obnoxious on decel, you can hear it coming for miles.....doesn't backfire, but it pops and growls a lot.