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Carb jetting

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Hi I'm new to the forum world but need help with an issue, I just bought a 2000 cr250, I put a wiseco top end in it and want to upgrade my reeds to the boyesen pro series. Was told I will need to re jet my carb. So I figured I would rebuild it and re jet but I'm getting mixed answers on what jetting set up is right for those reeds, any help is appreciated as I'm new to the re building carb world. Thanks

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No two engines are ever the same. Before my engine rebuild on my 2000 cr250, my bike liked 45 pilot jet and a 172 main jet. After it liked a 45-48 pilot depending on weather conditions (I leave the 48 in all the time, would rather have it richer than leaner and a 175 main jet. I too have boyesen reeds. But many things affect your bike. I have always used this method below and been fine. I did throttle chops for the main jet. Go through all five gears with it pinned and pull the clutch in and hit the kill switch then pull the plug to look at it. For the needle the third position has always worked great for me. But 45-48 main and 172-180 should get you close. Stock I believe these bikes came with 48 pilot and 180 main.

how to confirm your pilot circuit setting

https://www.thumpertalk.com/index.php?/topic/271735-how-to-confirm-your-pilot-circuit-setting

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start on what you think will be the richer side of things and slowly lean it out.  

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