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How does plug look ? Stuff coming from power valve breather hose

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2016 yz250x Premix 40:1

Hey guys i have a few questions. New topend and a jd jetting kit red needle 3rd clip 175/45 i noticed a slight hanging idle i went to a 48 and its still there slightly not as bad tho

Also plug colour this was new 30 odd hrs ago its black and dry, Also some other kinda liquid coming from power valve breather hose

Just wondering what what best course of action would be with jetting etc and what is that stuff from the hose? 1st time it happened i thought it was water after washing it but this was after a ride and didn't go thru any mud or water

Thanks

 

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The plug looks rich, but it’s hard to get an accurate reading of jetting on an old plug. You’d have to do a plug chop to find where you stand jetting wise.

The PV breather tube just lets out air and premix from the PV. Nothing to worry about and normal. If it’s excessive, your jetting is too rich or you should choose an oil with a different flashpoint depending on what you ride. 

Got a lot of spooge coming out the exhaust?

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48 minutes ago, MaybeMe said:

The plug looks rich, but it’s hard to get an accurate reading of jetting on an old plug. You’d have to do a plug chop to find where you stand jetting wise.

The PV breather tube just lets out air and premix from the PV. Nothing to worry about and normal. If it’s excessive, your jetting is too rich or you should choose an oil with a different flashpoint depending on what you ride. 

Got a lot of spooge coming out the exhaust?

just have a slight bit around the exhaust nothing major running down it 

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That plug is WAY rich, either rich jetting or a too high flash point premix is used.

 

but before any attempts in fine tuning the jetting, first check & adjust your float to specs.

(even brand new of the showroom floor many YZ floats are set wrong)

 

Pilot jet and needle settings are best done by 'feel', then the main jet by coloration: http://www.braigasen.com/howtoread.htm

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What elevation and temperatures?

 

No air leaks? Shouldn’t be lean on idle with a 48.

 

How many turns on the screw.

 

 

Do a leak down test!

 

 

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What type of premix are you running?  I saw this same thing on my YZ125 and have always run Dominator.  Haven't been riding it much as of late but was always curious if I had a leaky head gasket, etc.  I have heard that Dominator tends to run "dirty" which will leave your PV gunked up, but this looks more like water + oil.  FWIW, I never had any issues with it though, even after rebuild with fresh gaskets, etc.  It was still there but bike ran fine.

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You look Rich by quite a bit... Remember to throttle chop to get an accurate reading elevation and temperature will play a huge factor in jetting, what could be spot on may be too lean if the temp drops 30 degrees, or too rich if you are riding up in elevation.

I have found the best thing to do is jet on about an 80 degree day at my home elevation, that will get me in the ball park for fine tuning if I feel it required.  

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Oil is motul 800 40:1 AS with 45 varied between 1 to 1 1/2 48 bout 1 1/2 to 2 turn out

Elevation is sea level temps where 15c the other day when i rode Summer temp here get to bout 40c + But i dont usually ride past 32 to 34c just to damn hot here in Australia

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AS previously mentioned it looks "Rich"

Best course of action for jetting is "Reading" and don't make too big of a change at once.

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