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HELP! 300ex doesnt run
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Posted by: 282ex

Ok so i have been having problems wiht my 300 for a little while now. It runs perfectly when it is just warming up, and when it gets hot it wont idle, and i have to keep the throttle pegged or else it will die, and sometimes that wont even keep it running. I can maybe make it a lap around a track going all out until it dies.
I just changed the stator and trigger coil and it didnt change at all. still has the same problem.
I then tore the carb down cleaned it out, checked to see if it was the jetting, and it was slightly rich but not enough to matter.
I have the following parts on it: Curtis sparks pipe, high compression piston, webcam, biggun CDI, mild port work, and an open airbox.
o yeah and i dont know if this has do do with anything, but i wanted to check if it was the cdi, so i put the stock one back on, and i revved it for abt. 15 sec and the stock cdi box popped and started to smoke.

Any Ideas as to what it might be would be greatly appreciated.

Posted by: 300maniac

jets man u need jets with the pipe plus no lid meens 132 main jet

Posted by: 282ex

I have it jetted correctly. It has a 138 because of all the motor work it has. and it ran fine for a yr and a half with that jetting.