tsargent4
07-17-2008, 06:02 PM
I have a 2003 400ex with a fresh build on it that includes: JE 10.8:1 (416cc) piston kit, Hotcam stg 2 race cam, Uni air filter w/ lid on, FMF Powerbomb header and Powercore 4 slip on. I live in southern (Bedford) Indiana and as of right now I am running my carb with a 165 Main, 40 pilot, and needle on 3rd slot. I have done trial and error continuously and can still not getting my jetting right. I have tried running a spark plug that is a step hotter and I do run 50/50 fuel (110 race fuel and 94 octane). Once the motor gets good and hot and I let it sit and idle for about 15 seconds it wants to idle down and die(It's not in the idle screw though, I am thinking I need a bigger pilot jet). Also when climbing a fairly big hill in 2nd gear it wants to lose momentum to the point I have to go wide open throttle to get up the hill, but it still struggles. My question is this, what jetting should I have? or try? do I need to get a DynoJet kit or FMF Power up kit? It is to the point I can't ride because I don't want to blow a fresh build just because the wrong jets were used. Any suggestions or help would be appreciated. I am looking for an answer from someone who KNOWS what they're talking about, not stupid answers. Thanks.