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Carburetor question

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I have 04 yz250 and I had a 182mj 50pj 4clipneedle. And the bike idles great bit at top speed sputters. So I went back to stock 180mj 42pj 4clip needle. The thing idles horribly but the other circuits else feel great! Now iv cleaned the carb once and my hanging idle didnt go away. So on the top cover of my carb where it says cr flat. It has a tiny opening. Like the cover worped on one side or something. My question is could this cause an air leak? And thats wahat is causing it to idle great with such rich settings it compensates for the slight air leak? Any help out there would be great thank you.

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Air leaks usually cause lean conditions, but since the choke runs into the area above the slide, then its possible.

More than likely, the gasket on the cover is out of the groove and forced the cover up.  I'm having a similar issue with a bike and was wondering the same thing.

So I'm going to take my own advice and replace my gasket, you replace yours and we'll compare notes!

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Gasket loos great.. if I put it flat on a table youd see one side does not sit flush. Also found a crack on the orher side. I repaired the crack . Someone before me dropped this carburetor. But i recently found out that there is a pilot air jet. So I think that may be causing my hanging idle. Im going to check the size later on today. But please let me know what you come up with and ill do the same thank you.

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Also found this. The throttle slide gasket. Engine must have eaten the part thats missing?

1399314510891.jpg

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Spray some brake cleaner in the gap and see if the idle changes. If it dies you've got a leak there and it's causing issues.

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I tryed that and no leaks. I just went thru the carb and cleaned everything with top dollar carb cleaner and compressed air. Everything is stock setting from the book. Runs amazing now absolutely perfect! But my fuel screw is 3 turns out on the dot. I know I should go next step on the pilot jet. But do you think 3 turns out will do? I really dont wanna mess with it anymore now that I got it dialed in.

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Is the fuel screw loose at all, or is the spring still putting tension on it, enough to hold it in place?

I've run one of mine at 3 turns out for years, no prob, but I've seen horror stories here about loosing them too.  Good Luck.

 

I didn't work on my carb tonight.  Worked on brakes and got thoroughly frustrated, still got an air bubble I can't work out... uuuggg.

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Yea its got tension I counted 6 turns in so half way out at 3. Thanks so much for your help glad I got it squared away. Breaks suck good luck with that lol

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Your bike looks great man, a lot like my '03 bike.

Well, I sealed my upper chamber, didn't make any difference.

When I pulled my pilot jet, its a 40, so I'm thinking I need a fatter jet for fixing my issue which is hanging idle, then stall.

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Ronbuell for your brakes zip tye the lever , under full pull pressure, to the bars and leave overnight See how it feels in the am.

I have no clue how it works but it made my spongy front feel brand new.

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I remember my old 04 I fell on the front break leaver. It lost all pressure. So i replaced the master cylinder and bled it and still wouldnt hold pressure no matter how many times I pumped it. I got so mad I just left it alone. Next day walked out to try it and it had full pressure. Worked perfectly no problems since. I still dont understand it.

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OnB, Never heard that one before... I may try it.

grat, Yeah, if bubbles work their way up the line, then it will work

 

My 03 has the lne routed under the front axle, so its hard to get bubbles to run up the line without taking the caliper off and letting it dangle, then backflushing it, which I did 3 times.  Gonna hit it again today... .

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Ronbuell it was quite the thread argument awhile back on the general topic section here in TT. Names being called etc just general nastiness about there is no way this will work as it defies explanation blah blah blah. There were a few people I trust saying it worked for them so I invested 1 zip Ty and an overnight and my lever is firm now for 2 months and about 10 hrs saddletime

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Grat124, looks can be deceiving with just 1 pic.  What does the insulator look like?  Also what fuel are you using?  I've noticed that my bikes seem to run a browner color on lower octane, whiter on higher octane.  From that angle, yours looks whiter.  Soot on the steel threaded portion is ok.

 

How does the bike run, still running good?  Does it backfire on decelleration, or just pop some?  Does it flatten out on top end, or does it bog on acceleration?

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Ronbuell thanks for your help. It ran great last time I took it out. Started it today with my wash plug still in. It flew out the back after 100 kicks. And idle was off. So I let it warm up took it down the street set idle and ran it thru all gears. It ran good but from half throttle 3rd 4th and 5th to full with a quick wack bogged bad. So id be in 5th going easy than wack it down to full and it would just bog and basically stop. I run 91 gas and my air filter is a little dirty. Im going to buy a no toil tomorrow.

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But I brought it back let my brother ride it and he said he didn't feel anything. So maybe it cleard out or its just in my head. Ill run it again tomorrow its too late to start it. Its sat probably a week so maybe it just needed to be cleared out. But im just scared or running lean.

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