As you may have read from a previous thread, I had a jetting issue that needed to be ironed out. Bottom line was that I was running too rich and I found this out by a trial run without the airbox sidecover on. Contrary to what I've read should have been the outcome, I definitely noticed an low to mid rpm power gain. I didn't notice much more on top, but it ran smoother since the mixture was better. I'm trying to decide whether I should vent the sidecover or go from a 160 main down to a 158. Any opinions?