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02 yz 250f questions

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Alright guys my buddy just picked up an 02 yz 250f it is already converted to an auto decompression cam but the problem is it runs like crud some times it starts first kick sometimes it takes 30 kicks I think its Carb related but I don't know what all the stock jets and settings should be if someone could give me those settings that would be great! it does have a power now and a boysen quick shot installed along with a busted fmf muffler

but here's what it does starting problems and once its warmed up it has a hard time idling with out choke and when you blip the throttle it cuts out and it runs rough. Thanks alot guys I know I should get a manual for it but the guy has no money lol

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Sounds like the carb just needs to be cleaned and the pilot jet replaced. You can clean the pilot jet but it's easier just to replace them. Guitar strings are pretty good at cleaning the pilot jet

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alright well pulled the Carb off and cleaned the hell out of it, tested the AP it shoots a tiny stream but I'm guessing its correct. I set the little screw on the bottom of the Carb to 2.5 turns out from all the way in. I believe its the fuel screw? This sucks not having a manual it still doesn't run right does anyone have the stock specs on what it all should be I need the stock settings for the fuel screw the idle and all the stock jetting sizes thanks alot guys

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well I messed with the fuel screw a bit and got it to start a little easyer and ran it down the street a bunch and it runs smooth and power full but it will not idle at all. I've turned the idle knob all kinds if ways doesn't do anything.? What to do?.

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awsome thanks a million I'll check it all tomorrow, and go from their any idea what the black knob (idle screw) should be?

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Ok all carb jets are stock but the main is a 180 and I got the pilot cleaned out and it starts 1 to 2 kicks and it idles but now the problem is it shoots fire and sparks after you rev it about 1/4 throttle + and it pops and snapps like a mofo so I'm guessing that's the fuel screw adjustment along with the broken muffler causing the pops and snapps from exhaust leaks. Am I on the right track?

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thats what I learned from reading so many post lol another problem is once its idleing and you give it a little throttle it tends to hang and sometime the rpms climb but the throttle cables are all smooth and it all snapps back into place..

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I GOT IT!!!!! I GOT IT!!!!! she purrs like a kitten now and rips like a savage beast! I started with turning the fuel screw till idle went up then turned down the idle screw and just kept doing that back and forth till it was perfect! Now my buddy needs to drop about $500 bucks into it and it will be trail ready!

Another question I have is gearing for the woods, would a 50tooth rear sproket help it in the tight trails for a little more low end? Stock it has a 48 I believe. Thanks guys!

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Another question I have is gearing for the woods, would a 50tooth rear sproket help it in the tight trails for a little more low end? Stock it has a 48 I believe. Thanks guys!

50T or 51T works well for tight woods. 51T for heavyweights or high altitude.

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