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jd jetting question for 03' YZF 250

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I have a question about my new jd jetting kit. I recently jetted my 03' YZF 250 with my JD kit at an elevation of 400 feet and temp of 80 deg. I came up with a 180 for the main and then moved on to the needle. I tried the blue one in clip 5 and then 4 but I still seemed a tad rich. I wasn't sure if I should go to 3 since the instructions said that 5 was a baseline setting, so I installed the red needle in the 4 slot. This seemed very good but I was wondering if I would be better off using the blue needle in clip 3 since my altitude and temp are not extreme?

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From the blue marked needle in clip position #4, try using the red needle in the #5 clip positon. The richness is more likely from low throttle jetting and the red marked needle in clip #5 will lean this range, keeping the upper throttle pulling stronger.

The 80F temperature is about the point where I would transition to the leaner needle on your bike. This is with stock pilot jet, adjusting the fuel screw as needed.

Thanks,

James

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In my opinion I would try clip 3 with the blue needle. I tried the red in mine and it ran very clean. One problem though, I needed to find a mountain to roll off to crank it went it was hot. This was only thing that steers me away from the red needle. In my bike the blue needle has been superior, and for James he has top honors in book with his jet kit. 1st class product! :thumbsup:

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I ended up liking the red needle in the 4th clip pos. the best, it ran the cleanest through the rev range. I have not had any starting problems though. The 5th clip pos. was a little rich at about 1/4 to 1/3 throttle. I am about the same altitude as you and temps were 75 to 80.

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