I had similar problems. My filter was over oiled. It really doesn't take much oil beyond a few drops. I do not know about any leak issues or really what your bog sounds/looks like. Mine was right at the start of movement on the throttle and I had a big jump in power between 1/2 to full throttle. It was like a turbo kicking in. I cleaned the filter and that corrected a lot of it. I then went and rest my needles and convinced myself that I didn't need to move them beyond 1/4 turn in either direction to get a good tune. I also let my idle screw just keep the engine running as I began my tune. I used my LSN to really control the rpms at idle. The majority of my bogging and the jump in rpms were fixed at that point. I did listen to others on here and installed a pipe to further help the low rpm grunt. The pipe has thus far been a huge jump in performance. I am no pro by any stretch so I had to rely on the expertise here and everyone was very helpful. My tuning thread isn't that old and it may help you out if you look it over.