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Newbie

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Carb problems
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I recently purchased an 02 ttr250 that had been sitting for a couple years. It had an fmf exhaust and top of airbox cut up, but factory jets in carb. I replaced the exhaust and airbox with factory items then cleaned the carb. Had to replace all orings, accelerator pump diaphragm, needle and seat. The mixture screw was set at 2.5 turns so I put it back there. I noticed when testing the accelerator pump that the stream sprays into the side of the carb rather than down the "throat" is this normal?. 

 

The reason I ask is the bike runs great except for a bog when first applying throttle from an idle and some surging at low rpms. The bog and surging is so bad that I have trouble enjoying the bike and find myself not wanting to ride it. If its not the accelerator pump stream could it be the lean factory jetting, or maybe the needle heignt not set right ( I dont know the factory location for the needle and the PO may have changed it). 

 

Thanks in advance for any information.

 

 



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Guru

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Fuel spray is correct once air is going through it atomises better .

I had the same flat spot left main jet standard and went up one size on the idle jet and it's spot on 



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Thanks, I will try that. What was the next size up on the idle jet? I may just drill it rather than buying a jet. Have a set of index bits

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Guru

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I also went up a size on the idle jet to cure a problem just above idle.

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2004 TTR250. White Brothers E series exhaust, modded airbox, rejetted, 13/48 c&s & many more mods..



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Same, went to a 52 pilot and no hesitation off idle at all.

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