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Need help from the Jetting Gods

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I have had an 05 CRF250x for about 2 months. Love the bike but hate the bog you get when you hit the throttle quickly. I came off of a 2 stroke that reacted immediately when you yanked the throttle. I am not good at anticipating those things that jump in front of you on the trail(rocks, logs, mud holes) I had rather react not anticipate.

I have read threads for hours regarding bog, boyesen, leak jets, timing the squirt--my head hurts :banghead: and I am more confused than before. My bike is a 49 state x that is stock. What steps should I take in what order to try and eliminate this issue?

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patience with your jetting can minimize it, although I'm not sure it will ever disppear.

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The bog can be completely eliminated. I know you say you've done a lot of reading, but if you haven't read this ( https://thumpertalk.com/forum/forumdisplay.php?f=104 ), then you are missing the core of the problem. It was written with the YZF in mind, but you have the same carb on your CRF.

Tell us what steps you've taken, and what your results are, and maybe we can step you through it.

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Wow--much more information to digest. I appreciate the info. Barton I have not tried anything yet because I came from working on a 2 stroke KTM to this CRF. Getting to anything on this bike is much more difficult so I want to make sure I have a game plan before I start.

I had not read the posts you listed. I was only searching in the CRF 250 forum. I will let you know once I get through all these posts. Thanks again.

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The key seems to be getting the right squirt duration to the carb at the right time. The most important things to get right are:

The adjustment of the pilot circuit (fuel screw, pilot jet)

The clip position

The squirt timing

The squirt duration.

Once you get the pilot circuit and clip position in their best positions (crisp idle, and smooth power from 0-2/3 throttle), then you want to set your squirt timing so that the AP squirt just misses the slide.

Once that is done, you need to get the AP squirt duration set to 0.5 - 1.0 sec. If your bike has a leak jet (most newer FCR carbs do, it's the brass jet in the bottom of the carb bowl), changing this jet adjusts the squirt duration. A larger leak jet leads to a shorter squirt, and a smaller leak jet leads to a longer squirt. Most people (on Yamaha's anyway) end up with at #40 leak jet. Your mileage may vary on your CRF, but at least now you know it can be done.

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