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Dirt bike runs only when choke is on

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I have a Honda xr80r 2002 and I recently replaced the carburetor and it was working fine and ran without the choke on but now it's not running hardly at all with out the choke on. I can drive it but when I do it will only drive with the choke on and it barely accelerates and bogges out a lot and won't go up to full speed and when I give it gas it sounds like it's gasping for something. I have also tried to modify the fuel/ air screws on the carburetor. Please anything will help. Thanks. 

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Did you make sure you got the carb boots tight on both sides of the carburetor? The choke makes the bike run rich so it will start easier, it sounds like you may have an air leak somewhere. Check the carb and make sure you got all the screws and all the gaskets in place, check the air filter and make sure its seated correctly. 

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8 hours ago, Muffintop said:

Did you make sure you got the carb boots tight on both sides of the carburetor? The choke makes the bike run rich so it will start easier, it sounds like you may have an air leak somewhere. Check the carb and make sure you got all the screws and all the gaskets in place, check the air filter and make sure its seated correctly. 

Agree.

Start the bike and try to spray some brake cleaner or start pilot arond the manifold between carb and head.

When it's reving up instantly you got an airleak. Check for loose screws and check the manifold at all. Those intakes like to crack with the years.

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Did you pull the pilot and blow compressed air through it, then hold it up to the light so you can see through it?

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I didn't blow compressed air through the carb so I could see through it but I sprayed carb cleaner through it and I could see through it 

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I was talking about the intake manifold (Start Pilot helps starting engines - https://www.amazon.de/Holts-101130-START-PILOT-300ML/dp/B0027DD7QC )

Forget about the pilot jet, doesn't lead to symptoms like this.

Take off the manifold and look for cracks. Use a paper gasket at the head and a good O-Ring at the carb. A bit of grease will help sealing. Faces have to be clean.

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Plugged pilot, means not getting fuel on the bottom (lean).  Since it's a butterfly choke, cut air to compensate.  But, he bought it on Ebay.  That's the problem.  Good paper weights or something to shoot at 50 yards, but not good carbs.

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It's starting to run better but I still don't think it's to full potential. Where is the manifold located so I can check but I did the pilot jet and it made it run better 

Thanks socalxr and Alex for helping me out guys. What should my next step be 

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My gf's son's '05 crf50f gave me hell for a long ass time, wouldn't stay running no matter what I did. Thought I had checked everything, but there was 1 thing I left out, the petcock. It was damn near clogged completely shut. 

Pull the fuel line off the petcock and see how well the gas is flowing out. If it seems to be a weak flow, pull the petcock off the tank and try cleaning it out. 

If you have drill and tap abilities, you can get a rebuild kit, open up the petcock and really clean it out good, and put back together. Or you can buy a new one if the petcock is the problem, but Honda is proud of them. Unsure about ones on ebay though. Hope this might've helped 

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On 7/13/2017 at 9:03 PM, Parker Tims said:

I have a Honda xr80r 2002 and I recently replaced the carburetor and it was working fine and ran without the choke on but now it's not running hardly at all with out the choke on. I can drive it but when I do it will only drive with the choke on and it barely accelerates and bogges out a lot and won't go up to full speed and when I give it gas it sounds like it's gasping for something. I have also tried to modify the fuel/ air screws on the carburetor. Please anything will help. Thanks. 

Classic symptom of a clogged pilot jet circuit. Easy fix. Remove the carb, remove the float, and all of the jets. PUT ON SAFETY GOGGLES !!!!  Now spray carb cleaner thought each individual jet until it discharges from all the tiny holes. Before putting the jets back in, aim a flashlight into the carb throat and look from the bottom, and you should see light through the tiny ports, making sure none of the ports in the carb body are clogged. Reassemble, set your idle screw initially about 1/5 turns. It should now start and idle on it's own.

Edited by HomerDodd

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On 7/14/2017 at 10:16 AM, Parker Tims said:

What is the pilot jet and where is it. 

Here is a picture. Most pilots are taller and sit further in the bowl. Pilots and main jets can usually be removed. However, some carbs have pressed in jet's (like the picture below). . Not to worry. Still can be sprayed clean. If really full of crud, use a thin wire or very small welding tip cleaner to shove there, followed by spray or compress air.

CarbJets.jpg

Edited by HomerDodd

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