I have a 2001 (SP1). Been riding it for a couple months now. It has a power commander and slips ons. Here in the last few days it started running funny. Wont idle, sounds like its only firing on 1 cylinder, black smoke out of the left exhaust (rich mixture), I have to manipulate the throttle when sitting to keep it from cutting off and when I decel its almost like the engine switch is off (falls on its face)......all this and the FI light isnt on. The problem comes and goes with no rhyme or reason. I replaced the fuel pressure regulator with a brand new one thinking this was the prob. but it wasnt. Ive pretty much narrowed it down to what I believe is a fuel delivery issue....any ideas?