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Is about a spark plug from my mum exc 250 2011.

Jetting: 42p N8RH#3 175 main AS1.5

Temp around 8C 

Alt 500m

 

For me seams a bit gray= lean but I can feel it lean. 

To make more brownie the spark plug i need to rich up a bit jetting,but where?

Or is ok how it Is? -from  spark plug colour?

20180202_205327.jpg

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Unless you're mum rides WO id say check your needle may be on leanest setting clip in top grove. Or to lean pilot,  what fuel does she run? Make sure intake boot isn't leaking also

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8 minutes ago, Motox367 said:

Unless you're mum rides WO id say check your needle may be on leanest setting clip in top grove. Or to lean pilot,  what fuel does she run? Make sure intake boot isn't leaking also

See my notes. I don't think my bike is on lean settings,but I start to think about fuel, something is in there why I can't obtain brownie colour.

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8 minutes ago, adriano.ro said:

See my notes. I don't think my bike is on lean settings,but I start to think about fuel, something is in there why I can't obtain brownie colour.

What oil and ratio you use? Just curious 

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7 minutes ago, Motox367 said:

What oil and ratio you use? Just curious 

BelRay sin7 , 50:1

Edited by adriano.ro

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22 minutes ago, adriano.ro said:

Standard 95 RON pump fuel.

Location: Romania, EU.

 

Got it. Makes a difference as in 'what is in your gas'

15 minutes ago, adriano.ro said:

See my notes. I don't think my bike is on lean settings,but I start to think about fuel, something is in there why I can't obtain brownie colour.

Basic color looks fine, if anything, it is dark for a bike being raced but fine for a bike being ridden on trails and general riding where you run hard for a bit then just 'motor along'. See the link I provided before. Tip is really only at idle. The harder you run the engine, the deeper in the plug the color matters, hence pros using a lighted magnifier to see inside or they cut the insulator off a new plug after a chop. It can get expensive real fast. I use the same tool a Dr. uses to look in your ear. Cheaper tools like this can be found:

5a74d6b9203af_POW3010801.jpg.e8202a13ce4086cd7415dfd98fb60fbb.jpg

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How does it start and idle when it is cold or hot? You would make Pilot jet changes and float level checks if it doesnt start with first or second kick or doesnt idle without blipping throttle.
Another easy thing to do is drop the clip on the needle (raises the Needle) to make it richer at 1/8 to about 3/4 throttle...you should feel an obvious stuttering miss if that position if it is too rich. If not, then you may have been too lean.
Can do the same WOT to test Main jet

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3 hours ago, breakwellmz said:

Looks lean to me.Start by raising the slide needle one notch.

I consider that. 

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6 hours ago, adriano.ro said:

I consider that. 

So, in 4# clip will pull like a train! But is a bit too rich on stady throttle.  I need 0.5 clip leaner needle.

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Make sure there are no air leaks. I would step up the main 1 or 2 sizes and then look again. Make sure timing is not advanced. Is the jetting stock? at 50:1 and no jetting changes makes an engine run rich. 

CR

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