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jetting trouble with a yz325

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i finally got my 2002 yz250 with a esr 325 kit on it together after rebuilding the whole bike. i started it today but initially it would start then instantly die. i tried adjusting the idle screw but it didn't seem to do much. i was able to keep it running by giving it gas when i started it. but it will wouldn't idle by itself even with the choke on. so i moved the needle clip down one from the top position to the 4th position but it didn't seem to help much, still wouldn't idle. the throtlle cable is adjusted all the way loose on the throttle so i'm sure i couldn't tighten it to get it to idle but i don't think that's the right way to fix it. i'm running a 142 main and 42 pilot which should be a little rich from what i hear from other people with the 325 kit

 

 

 

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moved the clip down 1 more position( middle ) didn't seem to help. i rode it up and down the street a little and it sputtered reallly bad once i got past 1/4 open throttle

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Needle does not effect idle. Just the pilot jet and for fine adjustment, the air screw.

 

Just off of idle is the needle stright diameter. Then about 1/4 throttle up is the taper and needle length (clip position is for fine adjustment)

 

Then just before and at WOT it is the main jet.

 

Affecting all of this too is the fuel/oil ration. More oil needs richer jetting. Less oil needs leaner jetting.

 

 

Get the idle right before you move forward.

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thanks for the help, turns out the head of the idle bolt broken, but still being held on by the spring and little plastic tip, so i wasn't getting any adjustment on the screw. i replaced it and put the needle clip in the original position. it idles fine now and runs pretty good( at sealevel at least) little rich at about 50% throttle so i'll prob have to try another needle

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rode it today and it was great off the bottom, and ok up top but it had no mid range at all, like it just died after i got off the bottom. wouldn't pull at all like it just wouldn't rev. thinking its just really rich in the mid but it seems like it might be too much to even jet for

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