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03 250 carb question

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I have a new to me 03 CR 250.  I am new to 2 strokes so need a little help.  The bike had a sputter off idle to 3/4 throttle when I got it.  I had a JD jet kit with the blue (rich) needle on the 3rd groove.  It had a 400 main with the 32.5 pilot from the kit.  I changed to the red needle on the 3rd groove and it eliminated the sputter totally.  The bike had great top end before and still does.  The problem now is it had a high idle and seems to hang there especially after revving.  Once it stayed revved for a while so I shut it down.  I had read somewhere before what caused this but can't find it now.  Thanks

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Have you checked for air leaks? Did it idle high before the needle change? If so did you try turning the idle down?

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I didn't find any air leaks, and no it idled good before the needle change.  I tried adjusting the idle and got it down some but it is still high.  I can idle it down with the air screw, max idle is between 1.5-1.75 turns out.  It idle is better at 1 turn out.  It still starts first kick, I am running 32:1 mix.   I am just scared to get it too lean, like I said I am new to 2 strokes.  I have had 4 strokes forever and can jet them no problem.  Just nervous with the smoker.

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My experience with the mikuni JD needles about 8-9 years ago I found the red needle to be on the lean side in the 0-1/4 throttle range. I ran the blue needle for a while & had better results. If your at 1 turn out on the air screw that means you need to go one step richer on the PJ. The high idle is an indicator your on the lean side & could cause damage to your motor. I'd go back to the blue needle & try it on the 2nd clip position (leaner). That should clean up the 1/4 - 3/4 throttle range you mention sputtered before in the middle clip position. You can then adjust the air screw for the 0-1/4 range to dial it in.

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My experience with the mikuni JD needles about 8-9 years ago I found the red needle to be on the lean side in the 0-1/4 throttle range. I ran the blue needle for a while & had better results. If your at 1 turn out on the air screw that means you need to go one step richer on the PJ. The high idle is an indicator your on the lean side & could cause damage to your motor. I'd go back to the blue needle & try it on the 2nd clip position (leaner). That should clean up the 1/4 - 3/4 throttle range you mention sputtered before in the middle clip position. You can then adjust the air screw for the 0-1/4 range to dial it in.

This is good advise.

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