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Here's my plug, what to do?

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This is the second plug that has fouled since the weather has warmed (70° in NC). 07 300xcw using Amsoil Dominator 50:1, Lectron carb standard rod set a quarter turn richer. I have new moto tassinari V4 reeds on the way and will install them tomorrow or Thursday. I'm not an experienced tuner so that's why I'm asking....but I would like to learn so thanks for any help.

The plug in the pic might have 2 hrs on it....

20170411_192129.jpg

Edited by Paul T

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Its wet and black, so as a wild guess, I'd say you are rich at whatever throttle setting you were using.

But, this is a big but, you can't read a plug at the angle of the photo. You need to be looking for subtle coloring differences and you look where the white ceramic insulator meets the metal shell, way up inside. And you need to do a proper "plug chop" on a new or newish plug. What you want is a light tan color in the bottom of the ceramic, maybe 1/16 to 1/8" high.

There is no point in looking at the ceramic near the tip of the plug.

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I have not. All I have done is richen the the carb by turning the metering rod in a quarter, or half, of a turn back in November because the bike had a slight hesitation at low rpm to wot. 

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3 hours ago, GasitandCrash said:

Here is what NGK has to say on the subject

And of course, they are right for the basics. But for serious tuning, you have to look inside.

From the outside, you can see the big stuff. Like little tiny aluminum balls.....

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9 hours ago, Paul T said:

This is the second plug that has fouled since the weather has warmed (70° in NC). 07 300xcw using Amsoil Dominator 50:1, Lectron carb standard rod set a quarter turn richer. I have new moto tassinari V4 reeds on the way and will install them tomorrow or Thursday. I'm not an experienced tuner so that's why I'm asking....but I would like to learn so thanks for any help.

The plug in the pic might have 2 hrs on it....

20170411_192129.jpg

Warmer weather needs leaner jetting

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The Lectron is a forgiving carb for those of us that prefer them.  Yours is too rich, clearly.  There really isn't much need to adjust the Lectron for cooler/warmer weather once it is set up.  All 3 of my Lectrons came a little lean, they do take a little tuning to get just right imo.  Some guys get lucky enough to have them spot on from Lectron, it didn't work out that way for me.    

 

I'd start by going 1/2 turn leaner on the rod, then work in 1/4 turn increments.  Which rod are you running?  Have you checked with Lectron (or Slavens depending where you bought it) to make sure you have the correct rod?  

 

 

Edited by poldies4

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Reference the NGK chart, After further examination, I would  use that chart as an indicator of general trends, I would not use the photos as gospel concerning how the plugs look at various fuel/air mixtures.  For example, the plug that they show as a "Normal Condition" looks scary white, way too lean (too much air, not enough fuel).  The plug electrode should be free of particulate matter and have a light tan color.  None of the photos show what i would consider a plug with the proper mixture.

I found this link that discusses a "mixture ring" for two-stroke plugs, something I've never heard of (ignorance can be cured, stupidity is genetic). :

http://49ccscoot.proboards.com/thread/1727/spark-plug-reading-tuning-info?page=1

Is this what you are talking about?

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3 hours ago, GasitandCrash said:

is link that discusses a "mixture ring" for two-stroke plugs, something I've never heard of (ignorance can be cured, stupidity is genetic). :  http://49ccscoot.proboards.com/thread/1727/spark-plug-reading-tuning-info?page=1    Is this what you are talking about?

yes, exactly. Down where the white ceramic insulation meets the outer metal shell.
But the OP is way too rich, no need to worry about the mixture ring until he gets it closer to the right ballpark

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