I'm going to post this before I accidently delete it, but I have more to add. Ok, I'm done. Please fill out your profile, state or country, it will help us figure out your riding conditions. Like: what altitudes do you ride at? Mongle asked: 'The right one or the left one?' Do you have a 'left one', or is it a brass plug (a mirror will be needed if it's still stock with a flush plug). Jessepitt did this awesome photo essay: http://www.advrider.com/forums/showpost.php?p=18727385&postcount=71 Including pics of the brass plug, this is one of them. Stick around, someone will come up with the info to fixit. The RED is for those hard of reading. An easy way to tell if someone has been in the carb (which I doubt, too low mileage), is to look at the carb screws. A stock carb will have JIS screws (phillips look-a-likes). If you have allen heads (two on the top and two on the float bowl, you'll need a mirror), someone has been in the carb. The stock JIS screws are very tight, if your bit doesn't fit tight, you will strip them out. An impact wrench will help (one of those you hit with a hammer, not one with 6 hp and running on 175 pounds of air). Just to the left of the petcock vacuum is an allen head screw w/washer; not stock. Before you start, buy 4 replacement allen head screws at any good hardware store, the carb screws are 5 x 14 mm. Buy 4, two top, two bottom With mileage that poor and running lean; replace the pilot (fixes running better with the choke on), and these two o-rings (fixes your terrible mileage). They're metric and I'd suggest getting them from Zuki, Derek probably has them too. Pilot jet itty-bitty orifice. Leaky o-rings, murdered by ethanol. A light coat of grease will help the float assembly slip back into place. None of my bikes have ever seen a dyno. Drain the old fuel, add something like Sea Foam to help clean where you can't see. This is normally the first step, but it sounds like the pilot is pretty much plugged. You said that you just want to ride, clean the carb, replace the pilot jet, two o-rings and put it back together stock. There are many of us happy with the stock stuff. If you get a lean surge, we'll talk about that later. As JagLite said, "Ain't necessarily true." Pilot jet. Check the filter while you're in there. The rest of the story: http://www.advrider.com/forums/showpost.php?p=17527454&postcount=52 If you're good with tools, yer golden. If not, all bets are off. You don't have to read the whole thing, but there are lotsa pritty pictures, and you will learn lots. OBTW: Mongle is withholding information; many of the pics in the link are KTM BST-40. Just be aware there are differences, yours won't be identical.