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Another Jetting Scenario - Sorry

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Info: 99 XR400, 440 kit, Gordon Mods completed. It HAD the stock exhaust until this past weekend. I got a decent price on a FMF Power IV w/PowerBomb header ($340 for both). I installed both the header and exhaust. Sounds great… My problem is the much noted, ever nagging bog when rapping the throttle. It was not present before putting on the exhaust and header. (Elevation ranges from sea level to 4000’ ft.) I checked out FMF’s website for recommendations for jetting. 162/62 is what they suggest for jets. I took apart the carb apart and saw that it had 168/60 for the jets and the clip was in the 4th position from the top. Before I put the exhaust on, it really did run great. Although I never really worked on the bike myself, the shop I took it to for tune-ups and oil changes always said nothing was wrong with it. I changed out the pilot jet to the “recommended” 62 With leaving the other jet/needle alone. My thought it ran great before, the pilot change was for the exhaust. The bike runs strong, but only AFTER getting it going. It has the NOTICEABLE bog from idle. I have to “ease into” or roll the throttle to get it going. Once it’s going, I feel everything is doing good… Any suggestions??? Should I have jetted down on the main? Changed the needle position??? Seems like the third notch is the ticket… Tonight my plan is to start the ¼ turn increment routine as listed in other postings… I was just hoping for some verbal encouragement….

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Seems too rich to me. I'd drop the needle back to 3rd from top(stock)and change the main to 160 or 162. Be sure to readjust the fuel screw for best idle and off-idle response in a range of about 1.5- 2.5 turns out.

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