Vtxoa.com didn't have an answer? Try texasxriders. I know those guys will help.
Nothing's happened in that carb has it? I had that same bike (color, intake, v&H pipes) and it never made that sound. I does sound like it's missing, but it idles ok, so it makes me wonder if something isn't completely plugged in or if there is some other blockage somewhere. Did you remove the reed valves, by chance? I don't think that would be a problem, but anything can happen, right? If you join the texasxriders board, PM j1mmyj4m. That's my friend Brock. If he can't help, he'll be able to point you in the right direction pretty quickly.
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