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High elevation jetting tips

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Planning a ride up in the Kennedy Meadows area soon. I have a O2 YZ 250 With a FMF Gnarly pipe and a FMF Turbine Core 2 spark arrestor no other motor work. Only had the bike for a short time not sure yet of the current carb set up.

Anyway I think the elevation in that area is anywhere from 5000' - 8500' temps have been hitting 80 degrees up there.

What would be a good baseline jetting set up?

Here are some pics of the new ride.

http://www.villagephotos.com/pubbrowse.asp?folder_id=1727853

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You always want to go leaner at higher elev. depending on temp. My bike has a 48 pilot when goto higher elev. i have to goto 45 and i dropped my needle a notch or raised the the clip. I would have tried a leaner main but i didn't have one and i would have gone to a leaner pilot as well. I was ridding at about 4000' comming from sea level and it is still running a little rich. the goo comming out if my pipe was dripping down my silencer.

You always want to do a plug check to be sure you are not running lean.

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I have an 06 YZ with a FMF Gnarly and Turbine 2 SA.

When at 8000ft, last weekend, I ran a 165 main, 45 pilot, with a CJ needle in the middle position.

No complaints with performance, other than the loose nut at the controls.

I will run the same set up this weekend at an Enduro.

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N3EJ#2 is the stock needle and position for an '06 yz250. The N3CJ is a half a clip position leaner if it were in clip #2 from the top. N3CJ #3 (middle clip position) is a half a clip position richer than stock.

I'm am certain that the N3CJ is 1/2 a clip position leaner than the N3EJ and I'm pretty sure that clip position #2 on the N3EJ is stock for the 2006 yz 250.

However, if the N3EJ is in clip position #3 then that needle would be 1/2 a clip position richer than the N3CJ #3.

Clear as mud right...?!

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