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Jetting a CRF 250-X for NC

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Anyone in NC with a 250X that can offer jetting advice? I'm in central NC where the elevation is around 800 feet above sea level if I've been told corrrectly.

I have cut the top of the air box out, removed the diffuser from the muffler and it has a Power Bowl or what ever its called from Boyesen, otherwise the bike is stock. It runs great off the bottom but has a burp or stall in the higher rev range when cracking the throttle too quickly.

This bike started it's life in Idaho which was 5000-9000 feet above sea level if I remember correctly.

Thanks!

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I would just buy a JD jet kit, it comes with everything you need and instructions for setup. My bike is similar and I have a 160MJ, 42PJ, fuel screw at 2 turns out.

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I vote the JD jet kit too. If you ever change out the exhaust and go to a Twin air filter or equivalent, you'll already have the 165 to move up too.

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I vote the JD jet kit too. If you ever change out the exhaust and go to a Twin air filter or equivalent, you'll already have the 165 to move up too.

Do you have an FMF or another brand of pipe? I've heard the difference is great and I've heard don't bother. What do you think?

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I have a 2005 250r exhaust with a PromotoBillet tip/spark arrestor. I never jetted the bike without the new exhaust...I did all the mods and jetted it all at once and was able to go up to a 165 main (the max size main jet in the kit).

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Check the link for a helpful chart put together by Rick Ramsey. He's got lots of other CRF250X mods too.

http://www.rickramsey.net/CRF250Xjetting.htm

He mentions the chart does not apply to '07 or '08. But if your bike's and '06 or older, based on your altitude, it suggests 42 pilot. Since you've opened the intake and exhaust, 135 main and clip on the 5th slot.

Magic Racing is one place that sells individual jets for the Keihen carb for about $5 each. Or you can buy the JD kit and you'll have a variety of jet sizes, but you'll probably end up using just one or two.

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