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04 kx 250f only run on choke

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Hey guys I got a 04 kx250f  had top end redone vaulves adjusted and shimed new cam tensoner and chain did heat cycles ran without choke but had to keep it going with throttle my pilot was a 40 at the time guy told me to go to 42 ordered on while waiting for that brought it to a local shop the diassembled the carb and they did a ultrasonic dip now will only start on choke and will die with choke off guy that rebuilt it says it prob spun a cam wich is common with this year but haven't even riden it just a rip down the drive way befor I took carb to get that stuff done since I put the 42 and got the dip it's been like this..

 

Checked for air leaks all good there

Fuel.screw.2 turns out tryed 2 1/2 also

Played with ideal nothing shut choke off it dies the carb slide is assembled right Help

Checked for air leaks

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my 05 did this when i first got it , would only idle on choke . turns out the shop the previous owner had sent the carb to had installed the vacum relief plate int he carb upside down.  took it part put it back int he right way and bike has ran perfect ever since 

Edited by project89

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Read through what you've said / done.

 

The symptom is typical of a fouled fuel system on an old machine. To fix this, start at the tank. You can clean the carb but a dirty tank and old flaky hose will just clog it again. Dump the fuel, remove the tank valve and filter. Take them apart and clean them. Flush/rinse the fuel tank. Replace the fuel hose, NEW.

Next go through the carb again. Take all apart and thoroughly clean it. Blow through all tiny ports. Back blow through float valve seat to clear/clean the internal filter in the carb. Install NEW size 42 pilot jet. Do not try to clean it. Put a 3 mm allen key wrench under the throttle slide as a gauge, adjust the idle speed screw to where it just lifts off the allen key. Set the fuel screw at 2 1/4 out. Triple check the hot start plunger is moving freely, not sticking, and the boot is sealed not leaking. Check the carb to head boot for cracks/leaks. Reinstall everything and go for start. Come back here when you are done, gleefully report your success.

 

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Ok will do I'll report back now it will just pop like it wants to start but dosnt start started first kick last night with choke now it won't start it wants to but wont

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Dos it sound like a spun cam?that's my bi g qustion that what the tech told me but when he put it togeather he said it was all good it ran ok all up to the ultra dip and the 42 pilot and like I said it has maybe 30 min on it ideil for the 3 heat sesons after rebuild

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It does not sound like a spun cam at this point. Just a clogged fuel system.

If you are concerned about that it is quite easy to check. You need to remove the valve cover and then take some pictures of the cams for us to look at and we can tell you if spun or not. What you would be looking for is that the circle hole on the cam gear is aligned with the peak of the lobes on the camshaft

 

 

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Alright I brought it to a guy I know he drained the bowl it fired without and ideal with choke but dosnt ideIL have to keep throttle going but it was a step foward I'm ganna do all this things on thur I'll let u guys know

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Get a BRAND NEW pilot jet.
Worth the investment.
Chokes hold back air to richen. You have too much air and not enough gas. Hence, clogged pilot. If you have to take away air (choke) to run, that means you need more fuel. You're not getting enough fuel cause the holes too small cause its dirty.
Get new jets. I bet its a ten year old bike.

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I have a brand new 42 I just put in it so I should buy a another one? It will start off choke now idk why but won't idel I'm ganna drain all my gas and clean tank take carb apart clean it once again and inspect it my float hight is good checked it yesterday ganna blast every hole I see on the damn carb I'll have results tommorow

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I have a brand new 42 I just put in it so I should buy a another one? It will start off choke now idk why but won't idel I'm ganna drain all my gas and clean tank take carb apart clean it once again and inspect it my float hight is good checked it yesterday ganna blast every hole I see on the damn carb I'll have results tommorow


Good. Be sure to not miss anything. Come back here and reread, make a checklist if you need to.

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Alright guys got everything going plug was totally black it had a new plug and I tip my carb upside down than I see the gas in all the breathers than I drain but I have to keep tiping carb upside down to get gas to drain out of carb?never did that befor all of it would just come out on its own? What's that all about

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Old o ring from fuel adjust got other broken half out so there was one broken o ring with a  down there with half floating  around ganna clean carb cleaned tank new hoses let u guys know how it gos

20170928_112711.jpg

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7 hours ago, Jimmy Day said:

Old o ring from fuel adjust got other broken half out so there was one broken o ring with a  down there with half floating  around ganna clean carb cleaned tank new hoses let u guys know how it gos

20170928_112711.jpg

 

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Cleaned carb got that old o ring out cleaned tank and it idels!!!!!thank u guys for all ur help how many turns out should ideIL be tipicaly

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That's not the idle screw. That the fuel screw. And you start at 2.5 turns out from fully in. In is leaner. Out is richer.
The idle is a black plastic knob pointing sideways. On an 04 you'll need to turn idle up to start then a couple turns down once its warmed up. Listen for a happy idle rpm

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Ya I know I got a happy ideal I'm 2 1/4 turn out on fuel adjuster had ideIL nob all the way in till I got a good ideal how would u know if it was still lean.....would I put fuel adjuster so I get more gas than find a good idel and keep checking plug?

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I use the hot start response to fine tune the idle mix. I’ve posted my method on here a couple times. I am not near a computer for a couple days and a forum search copy/paste is difficult on my phone app. Perhaps you can find it, or some TT sleuth could find it copy/paste the text steps here for us. There are other videos on how to adjust the fuel screw. Imho my method gives a finer tunes and best results.

 

 

 

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well my bot start is disconnected because it won't ideil with it hooked up so my cable or spring isnide carb is junk so I can't use that right now

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Then you need to cleanup and get that hot start operating smoothly or you need to get a new one. Matters not whether you actually use the hot start or not, the components are part of the carb function and is needed to be in place for the carb to work properly as a system. Just as the choke button richens the fuel mix, the hot start does the opposite where it leans the fuel mix by bleeding air through a bypass.

 

PS: wondering why such difficulty to spell “idle” correctly.

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Cable just isn't hooked up its still on carb runs fine but ok are u offended by the way I spell this a spelling fourm too

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