Hello Eddie and everyone, I am new here and tried the search button for info...sorry, but can't find my particular problem yet....Really sorry if this is a beaten topic, I am just at my wits end. I have an '02 DRZ400E that ran beautifully with an open top airbox, the Ebay alloy end cap in the stock exhaust and a 165 Main jet, at six hundred feet above sea level.. No other mods. This thing ran crisp. This bike ran great, until I put a Yoshimura full Ti exhaust on it this am. (it's the PRO full Ti triangular muffler system) I raised the needle one notch, then returned it to the center position after bike wouldn't idle. (didn't think they were related but...) Now bike won't idle, unless idle adjust screw is bottomed against it's max input stop and then just barely. No more adjustment left on throttle stop/idle adjustment knob. It starts, but not easily, runs OK as far as revving in neutural. Just barely idles...What gives? This thing ran beautifully 'till I changed the exhaust. Checked all connections, but found nothing. I can't believe jetting would effect idle that much, but again, I am lost now. Any help appreciated! Thanks, Dave H.