04 crf 450r lean popping bad please help

i have installed new vales in spec seats cut and lapped with stainless vales 13.5:1 compression piston and a s2 hotcam and a big gun exhaust i finally started the bike today and it was a chore i had to have choke on and feed alot of fuel to it the fuel is brand new 110 octane race fuel i got it stared but pops alot more on decel and wont idel check all jets the are free and clear .

im thinking i need to rejet they are all stock jets in the carb with all this work im sure it needs jets right but where would i start?

my bike is pretty much the same as yours what elevation are you at? i'm at 430ft. went riding at 1300ft. the other day and my jetting worked fine 45pilot 172 main and my bike doesn't backfire or pop hope that helps. BRAD

im at about 1000 ft and that about where i ride i just did all of this work and have stock jetting so i know i need to jet it just dont know how much to go

start by checking the exhaust for leaks and make sure the slide is installed the correct direction in the carb

no leaks and carb was never taken apart

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