Hello,

I just got my 02 1200 Sportster, rode a few hundred miles, ran like crap at low rpms, took the carb off and cleaned it, helped a little, played with the idle mixture screw, helped a little. Then I heard a rattling sound and started poking around. Rear pipe was about to fall off, nuts were finger tight. Looked up spec, torqued front and rear exhaust flanges to spec, ran great. Here's the oddity, when idling, the rear seems 'off', valve sticking, cam timing, something. I can hold my hand over the pipe and feel it suck in hard, yet come off idle it runs normal, and really get on it on the highway and it's eyeball flattening. So logic is telling me there can't be anything terribly wrong, but something is off. On a side note, I am taking the Vance and Hines straight shots off next week and putting on a slightly modified stock exhaust. That's not to cure this problem, that's just to save my own eardrums. Ride two hours on this thing and you're deaf for a while. Any clues, recommendations? Thanks!