Guys, I'm so damn happy right now I have to share! I have an '01 426. My bike has never had an off-idle "stumble" or bog off-idle (at least when the fuel screw was adjusted right ). Until recently. The last 2 weekends I've noticed a bog off idle that I couldn't get rid of with fuel screw adjustments. I'd turn it in to lean it out and get a hanging idle. Turn it out to richen it and it would get worse. Arrgh. Did I over-oil the last two air filters? I noticed the last time I put one on it was pretty heavily coated. So I cleaned 'em up and *lightly* coated them with oil last night. I reinstalled one today, started the bike up, and damn if I didn't still have the bog. I messed with the fuel screw again and verified the same behavior as before. Crap. Now what? Well, since I had a feeling that I had over oiled the air filter, I took the carb completely apart and cleaned it real nice just now. Even installed the slide backward just for kicks. Once I redid the slide and got everything buttoned back up, I started the bike up. Wooohoooo! No more bog! Must have sucked some oil in the pilot air jet or sumpin' like that. Anyway, I thought I would share so the newer members can recognize these symptoms and start with a clean carb before they mess with jetting. BTW - my jetting is completely stock right now (about 65 degrees, sea level) with fuel screw adjustments daily to compensate for temperature.