crf 450 carb tuning 2003

having problem tuning my carb... yes i have read the manual.. the jets are right, valves are good.. still having trouble starting... needl is third from the bottom and pilot air screw is 1 3/4 turns out... and don't know about the air screw but it was turned way out... thats how i tuned it to low down the idle when i got it started... will start fine when its hot... in the manual it says 5th position for the needle and idk if its from the top or bottom... please help a little thanks

are you using full choke and 3 twist of throttle

Your poilt jet mite be getting clogged. Try a new one , and see how it acts. Over time they do get clogged with varnish.

I am gonna agree with tjg53 , your pilot jet is clogged , thank the Ethanol for that

If you have the proper jets for your altitude , and you read the manual and set everything to the recommended settings , then its either old/bad gas , or your pilot jet is clogged

in the manual it says for the needle position to be on the 5th spot... does it meet the 5th position from the bottom or top?

i would say from the top because it richens fuel you move the clip down

Needle clip position is counted top down. +1 on the recommendation to just switch out the pilot. That is a classic symptom for a clogged pilot (or fuel screw too far in).

BTW - there is no air screw. The fuel screw on a FCR carb is letting in more or less fuel in the pilot circuit , not air.

my bad i meant fuel screw... i'll try a new pilot and see whats going on with that...

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