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Very little change w air screw adjustment? 300xc

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Hi All,

 

I just bought a 2011 300 XC with gnarly pipe and fmf scilencer. Its my first two stroke and I'm loving it so far.  I'm currently working out some jetting issues and I am pretty close to getting it dialed in for my elevation. I am wondering about the air screw adjustment on this bike...  I don't seem to be able to lean the air screw enough to get the thing to act lean (almost stall) when I crack the throttle?  I have it backed out 3 turns and it won't go any further.  I do notice that when I screw it in it acts more rich to the point of bogging at about 1.5 turns in or so. It has a 35 pilot in it.  Is this an indication of float level being too high?

 

For the most part I seem to be running pretty rich and have dropped to a 160 MJ and the L needle dropped all the way. Its running great at this setting with only a tiny stutter at about 1/8" of throttle when cruising down the road at moderate speed.  Dropping the needle to the 1st position helped this tremendously but it is still there.  I'm unsure if this is a two stroke phenomena or not?  The settings I'm at seem to be two notches lower than the stock chart and one jet lower.  Its pretty dang good but I have some spooge coming down the exhaust still which is surprising considering I should be on the lean side of things I would think...

 

I am at 5000' and about 70 degrees.

 

Can anyone lend some insight?

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Normally the rule of thumb with pilot size is if you are under 1 full turn out on the air screw go up one size, over 2.5 turns out go leaner one size.  Of course start back over with A/S after the change - set correct idle speed and 1.5 out is a good starting point when swapping to a different pilot size.

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13 minutes ago, Mikek671 said:

Normally the rule of thumb with pilot size is if you are under 1 full turn out on the air screw go up one size, over 2.5 turns out go leaner one size.  Of course start back over with A/S after the change - set correct idle speed and 1.5 out is a good starting point when swapping to a different pilot size.

It sure acts like I need to go one size down on pilot but in reading over the forums/jetting databases, I am at the lowest pilot jet size already that I can tell. Seems like I should be able to lean it out and get it to fall flat off idle with that pilot size (35).

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Raise the  needle diameter and try it. It will lean the idle. 

 

 If you are far off and running the slide high (idle screw) the AS loses its impact.

 A loose squish can easily ruin low rpm running. 

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