I've been monkeying with my America for 12,000 miles, now. I removed 2 baffles, 130/45 for a few months. Went back to stock 42 pilots. After almost getting run over again (Tallahassee is a college town), I removed third baffle, installed TBS needles, and recently drilled airbox. I ride with earplugs, anyway, because of wind-in-helmet noise. 2 baffles out, as many have described, is deep and throaty, louder, but not obnoxious. 3rd baffle out added some bark, and of course, much louder. Especially at full throttle. Now, I have to take it easy in my neighborhood so the neighbors will still wave at me. Its still not ridiculous-Harley-straight-pipe loud.
The biggest performance gain for me was realized after removing the 3rd baffle. Right now, I've got 130 mains, 42 pilots, 3 1/2 turns out, 3 baffles out, no snorkle ('05s don't have the internal snorkles), and I drilled two 1" holes in bottom of airbox and connected them leaving 3/8" or so of material around perimeter of filter base. I've never had a large enough block of time to really fine-tune everything, but it runs pretty good. Time for my 12,000 mile valve check, I'll do it then. Wish I knew more about what I was doing. It's fun, though.
