EC 250 2008 jetting problem

mrfreezer

New member
Hi guys.. I need some help... I try to tune the jetting.. I Have slide #7
Pilot Jet #45
Main Jet #175
Needle N1EG on the leanest position

when I try to set idle I need to have Idle screw totally in and air screw just half a turn from fully closed. If I turn airscrew even 1/4 turn out idle starts to stick so it looks like it is lean. But on the other hand I have oil coming out from exhaust and my powervalve stick closed after riding a while in low RPM. I need to pull WOT to clean it and than it runs good, but lastly I tried to clean it with WOT and it fouled the plug and I needed to change it. Old plug has black electrode but the rest of plug looks totally clean. Can you help me with this? I have already received NEDW needle I ordered so I will try it today
 
I have swaped needle for NEDW... now I have airscrew 1.25 turns out from fully closed... Idle screw 0.5cm from fully closed.. idles perfectly... I have although cleaned PV, it was really dirty... I will test it tommorow.
 
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It will all be about finding the right clip position. Then adjusting around that, but that will be 80%.
 
If I put smaller pilot jet I will need less air.. so air screw will be closed more... Am I right?? I have found out, that my engine does not shut down if I turn AS fully in... that would mean I am still lean.. so I need bigger pilot jet... but maybe it is lean because my needle on the leanest position and idle screw turn in just so much, it is letting more air in, but no more fuel... and maybe ma sticking idle is not really sticking idle because of lean condition, but it is lowered idle because of rich mixture... I will try to change pilot jet to 42 and try to turn idle screw out to make it idle just with pilot jet and airscrew set properly and not by lifting the slide...
 
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Wound in means richer.
Sometimes you just have to try the different pilot, find the best position when warm riding it and compare with another adjusted as well.
 
So guys... I have solved it today... I had too big pilot jet... needle all the way down, so when I was lifting slide by idle screw, I was just adding air without fuel.. That was why I did not have to have airscrew turned out more than 1.5 turns... So today I started with turning idle screw out and turning airscrew out too.. I ended with idle screw just lighly touching the slide and air screw 4.5 turns out... so I swapped #45 pilot jet to #40 pilot jet... now I have airscrew almost 2 turns out from fully closed and idle screw just a little bit lifting slide... Bike now runs much better... it is like different bike... stable idle, no oil on exhaust, no sticky powervalve and much more power... thanks a lot.. I will write more after testing it for few hours...

here is a vid of my gasser idling...
https://youtu.be/P3CmEeXnjLI
 
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Today 4 hours of riding without problem... bike runs great.. idles good... no sticky powervalve... just a little oil on exhaust....
 
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