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2003 400ex carb jeting question

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so I bought my wife a 2003 400ex ran good for a short time and the head gasket went ive got that all fixed now but it gets hot quick so I got into the carb to find a 38 slow 162 fast and the idle air was still blocked off. the motor has been bored .50 over stock compression it has k&n drilled lid header and fmf slip on I drilled out the block off to the adjustment screw and wanted some advice from someone with more knowledge about what I should jet it at sea level thanks

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The 03 400ex came stock with #38 pilots, and a #148 main. Someone has upped that main jet already. I just bored out a trx450 0.030" over for a customer, and didn't have to change from the stock main or pilot. The idle air screw had to be about 3.25 turns out, but it worked great there. More than that I would have jumped up a size on the pilot. For yours, I wonder about your oil cooler. Partially plugged? What tells you it is getting hot? Is it melting plastic?

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