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hows it going everyone new forum member here. i have been riding for 2 years now my first bike was a 04 sv650 till it got totaled in a accident last year.:mad: now i just bought a 83 yamaha xj 750 maxim after selling a 91 honda ns50 for 1k $.:) been having some issues with the carbs the prevous owner was verry dumb and tried to adjust the idle mix screws and drove them all the way in till the tip got stuck in pilot hole and stripted the heads. so now i have the carbs sitting on a friends bench getting drilled out retapted and making new needles with a CNC lathe.:coffeescreen: we both did a couple sample needles today and cant wait for the finished product. been almost contimplating on building a small repair kit with custom made needles for people who have the same issue because you cant just go to the dealer anymore for a new carb.
 

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It sounds like you are on the path to recovery. If you have stripped out idle screws you are back to place one. Until that is resolved nothing else will matter. Once you get past that the rest of the setup should be fairly easy. Keep us in the loop as you move forward.
 

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Finaly got idle screws done today on the cnc lathe and they look and work amazing! Just got done making a manometer to sync carbs. I uses some extra 1/8 air tubing with a homemade manifold and some trans fluid. I may need to find some thinner fluid since the tube is so small. I was thinking of adding some dye to some pneumatic oil since its thinner and easier to get air bubbles out. Any body have any advice on setting idle screws other than sound. I ask because i dont have a gas analyzer to test each cylinder
 

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"Any body have any advice on setting idle screws other than sound. "

To judge an idle screw adjustment I use the tachometer function on a timing gun.
 

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As Eye said, for idle setting you are looking for an RPM response. Use what tools you have for that. When you get it right the idle will be right after RPM drops off and you return the screw to its previous setting where the idle was slightly higher. It is not magic. You are looking for an optimum air/fuel mix and when RPM drops off it tells you that you no longer have it. When you back off and the RPM returns to its previous value you have found it. You can do it by ear but it will not be as accurate. How good is your ear?
 
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