i have a 1980 kx 80. the bike starts within the first few kicks and idles fine on choke. i let it idle down until it comes to an even smooth idle, and the pipe is warm. i push the choke in and it revs back up really high then it idles down quickly and conks out. i try to give it throttle to recover it but it acts like its fuel starved. i can ride it around with the choke on and it stays running. i pulled the carb off of it and sprayed it out with carb cleaner, took the pilot jet out of the carb and cleaned that up and its all clear. replaced the spark plug, changed the air filter. i have no idea what else to do. please help !!!