Idle/Stalling/Glowing Pipe

So I took in a 03 YZ250f today    at first the idle was so off that it would not run without revving the throttle, played with a combo of the air mixture screw and idle screw to get it to idle just fine. So now I notice tonight with one last test that the header and inside of the muffler were glowing red, and getting more red as I revved while I sat in neutral. I rode it around in 2nd and it was still glowing, just not as much.

 

All this combined with the fact that my other concern is that when I get it revved up high (say top of third gear) then clutch and coast on it the engine kicks off and I have to kick her over again. Kicks over fine just after that but I'm wondering if all three of these issues are linked together?

Put in a new pilot jet to replace your corroded one.

Put you fuel scew at one turn, and drop the idle with the idle screw as low as it will go

Now raise the idle with the fuel scew.

 

You have a common problem: bad pilot causes a lean condition, making idling difficult, so you have to mis-adjust all the settings to get it to run, and it will run extra-lean, causing the glow.

the fuel screw is a fairly foreign concept to me,     what is the measuring point for "one turn"... from full in?

Edited by Moto477

cool! ill give it a shot tomorrow....that would cause it to stall when coasting?    wouldnt be a valve issue?  thats my biggest concern

cool! ill give it a shot tomorrow....that would cause it to stall when coasting?    wouldnt be a valve issue?  thats my biggest concern

 

Doubt it.

But yes, the valves have to be watched along with the cam chain and tensioner.

They wear, and need to be replaced before they wear out.

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