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Jetting question

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Hello, I just purchased an '07 KTM 250 XCF W/280 kit and full FMF exhaust W/powerbomb header. I rode the bike today for the first time and believe there are some jetting issues. I was wondering if I could get an idea of recommended jetting, needle position, and where to start with the air screw. Thank you! :bonk:

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Main issue was a pretty bad bog if throttle was chopped, bog was near the bottom, actually it was right on the bottom. I got some of the bog out with the air screw, the bike seemed to be running pretty rich, i could smell gas in the exhaust. When the bike would bog and stall (with a rekluse) it seemed the carb was maybe loading up, adding diffulculty in re-starting. I just got in this morning at 3 am with the bike and have no clue what the current jetting is. I am going the clean the carb in the morning so I will know then. I was just wanting to get kind of an idea of suggested jetting. Thank you! :bonk:

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Fuel screw (air screws are in two strokes) is for idle only.

Before you mess with a 'new to you' bike, you need to ride it properly, and do the basics first. Clean carb, new fuel. Note all current jetting. Then you can begin to set it up. Hot bike. First, set the fuel screw for a perfect idle. Then the main for strong, WOT pull in 4th gear, then the needle for good mid range. Then and only then, can you pay attention to any bog that occurs during normal riding.

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Thanks! Yep, I should have cleaned the carb before I rode it...just had to give her a go! Thanks again!

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Hey, cleaned carb, found deposits probably stopping gas flow. Tooled it around and bike is running fine. Current jetting is 42 pilot 172 main, is this ok? Thanks! Oh... is there any problem with running 100LL in this bike? I have been running it full strength in my YZ 290 smoker and really like it. What about 4 strokes...how would a 280 like it? Say 50/50 NE 93? Thanks!

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