Yo! New here! I am having the "die at [nearly] wide open throttle" problem on my Mototec Demon described here, but only randomly. So do you mean adjust the needle that is operated by the tange, or the main jet? Or do you mean the idle adjustment screw/needle? I am at altitude so I have the jet tuned as lean as possible...If it bogs down wants to die at wide open throttle then it's setup to lean and the needle needs to be raised up if fuel dumps out the over flow then the float hight needs to be adjusted by carefully bending the tang.
They are never properly setup from the factory the adjustments are part of dealership prep if you did not buy from a dealer then you have to adjust the carby yourself