Hello,

Having some jetting issues that I need help with. I bought my 12 year old daughter a 2018 KX 85 and a 2018 KX 100 (haven't touched this carb yet) that I have installed and FMF fatty pipe on and a FMF shorty silencer on to replace older bikes we has as she races on a regular basis. Let me start with the KX85 because this is the one I have been working on religiously for weeks. First off, I live in North Dakota, its roughly 70-85 degrees here right now and at about 1000' above sea level with little humidity this time of year. There is a new plug and clean air filter in the bike. From idle to approximately 1/8 throttle the bike bogs bad. Initially I tried the air screw method of turning the screw all the way in and then backing it out 1.5 turns. Start the bike, use idle screw to get a slight fast idle and adjust the air screw in just until the RPM raises. Then I ride the bike from 1/4 to 1/8 throttle and snap the throttle and then comes the bog. If I roll on the throttle slowly the bikes takes off like it should but that wont work coming out of the gate trying when daughter is trying to get a hole shot. Try adjusting the screw out and it gets worse. If I adjust screw in to about a 1/2 turn from seated the bog disappears but I know that this is below the 1 to 1.5 turns that is usually the norm. So I pulled the plug and its a whiteish color and the base of the insulator. I pull the carb and it has a 40 pilot jet and a 148 main from the factory. I know 148 main surprised me also as the owners manual stated it came with a 140 main, 38 pilot and a NRJC needle. Since my bog is from the snap of the throttle I changed the pilot to a 42 with no change. I then changed the pilot to a 45 with no change. Floats are good. The bike pulls and runs great once it gets past that bog so not so worried about the 148 main unless someone tells me otherwise. So now I'm at a loss. Should I keep going higher in pilots to get rid of this bog or what? Thanks