Back to the original topic... I am having a similar bog. I'm running 28pwk's also with stock engine, SLP pipes, air box w/ k&n pro design adapter, k&n lid and one 2 inch SLP vent in the box, +3 timing, and 40:1 castor 927 w/93 octane. 145 main, 48 pilot, jjh needle clip in 3rd position. Starts and idles good. Bogs out right away and wants to stall unless I keep the revs up. Once the big clears out everything is good. Thought it was a rich pilot so I went down to 45 pilots and 1 1/2 turns out. Bog is gone but I might be lean. Got stuck in a tight spot and started to overheat.