250 1988 yz250 build

You need to actually have the carburetor off the bike and or as Mike suggested turned sideways to see that the slide is INDEED bottomed. Lucky for you it is running rich as a pig. If it is missing the needle as mike asked about or the main jet it will do that too. anyway, make sure the idle screw is backed out to the point it makes no contact with the slide, and there there is slack left in the cable before you try to start it again. Getting to twist the throttle and feel what we have been talking about may help.
 
On the microfiche on page 5, is part number 15 secure? If the nut from the underside of the cap is missing it might be hanging the slide up when you roll the throttle back in!?!?
 
I'm not really sure... I'll check everything out tomorrow and see but when I drop the slide in the carb it goes in all the way and also when I twist the throttle I hear it come all the way up and can also hear it drop back in place. I'll check it out and take pics tomorrow
 
You sure you know which one I am talking about? If you really are talking about the IDLE screw, that ISN'T the way you set it!!!

I think in your green state you are confusing the low speed air screw with the idle screw. Before you go any further, kill someone or blow something up you should really go look at a schematic and see the difference in those two.

Then back the one that really is the idle screw Out until it is about to fall out. Then start it and I bet you found your problem.
 
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You sure you know which one I sm talking about? If you really are talking about the IDLE screw, that ISN'T the way you set it!!!

I think in your green state you are confusing the low speed air screw with the idle screw. Before you go any further, kill someone or blow something up you should really go look at a schematic and see the difference in those two.

Then back the one that really is the idle screw Out until it is about to fall out. Then start it and I bet you found your problem.
Hey Andy :wave: Please highlight numbers from the schematic for him and me? Guessing throttle screw #26 from this link if poss??? ( see next post)Please excuse my ignorance here!

:noidea:
Dang wrong fische lol
 
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18 is the throttle screw??? I thought it was a drain bolt!! Are you serious? You are talking about the big bolt at the bottom of the carb aren't you?
 
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