ive got a piped 300ex. it had a 42 pilot and 130 main which were both to rich for it. so i went down to a 40 pilot and 125 main. when i barely tap the throttle, like 1/12 throttle, and try to hold it there, its like kill switch. the engine just dies. no idea? little help?

300ex
white brothers full system, uni filter, riding about 1000 ft above sea lvl. thanks guys.