i have an 09 kx250f last time i rode was at a local track a couple weeks ago and the bikewas running flawlwssly. its aways fired right up first or second kick every time and i brought it home pressure washd it then wen to start it the next day and it wouldnt start. i took the pilot jet out cleaned it put it back in got it to start while i was holding throttle open adjusted the fuel screw and idle screw so it would start and idle first kick every time like it always has. so i think i solved my problem right? wrong. after i let it get cold i go to start it again wont start gotta do the same thing adjust the fuel screw and idle screw to get it to start idle and run how it should. i dont know why it wont fire up n run rightwhen its cold need help please! really stumped on this one!

You still have water contaminated fuel, possibly a wet air filter.

Jettting does not 'magically change'.

its not water in my fuel i drained it then put new gas in it yesterday. im guessing its probably a wet air filter

it was because an intake valve was tight