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400ex jetting
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Posted by: prnstr4life

I have a 400ex with a 12:1 high comp stock bore piston, stage 2 cam, open airbox. stock carb, hmf slip on. what do you all recomfor jetting at sea level running at 50-60 degrees

Posted by: Eviltanker

You could start with a 40 and a 158 for a start point. you might or might not have to go up from there.

Posted by: fastredrider44

I'm roughly at sea level, high humidity, and ride from 20-100 degrees. I have roughly the same mods as you and run a 155 main and a 38 pilot. Don't remember about my air/fuel mixture screw, but I adjust it time to time going threw the seasons.

Posted by: Eviltanker

Try 42 third clip and a 158 then do a plug chop. Let me know.