05 250X midrange bog

Rode my 05 CRF250X first time today. Throttle response is great at low rpm's but it has a bad bog mid throttle and up.

It has airbox cut, screen removed , pink wire mod, baffle removed,JD kit 165 main, blue needle in #4 position, fuel screw 2.25 turns out. Temps were 32 to 50 today. 1200' Any suggestions?

Dont know Mag. Wish i did. Having the same prob except at low throttle. Ill keep watching this post.

Try lowering the main jet to a #160 and set the idle mixture screw inwards to 2 turns with the blue marked needle. Keep the idle set slightly high with the fuel screw setting to have it running cleaner and make sure the bike is hot before testing.

Stock pilot jet is #40, correct?


Yes, stock slow jet is #40.


Try the suggestion above and if the condition doesn't improve, use the red marked needle in the 5th from top clip position.


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