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xr250l slow to return to idle

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I have a Honda XR 250L i purchased new in 1991. No modifications of any type have been made to the bike. From what I understand the bike is equipped with a pumper carb.  Recently I had to remove and clean the carb. I used a hypodermic needle to clean the jets. It took a good amount of force and twisting back and forth to clear all debris from the idle jet. After I reinstalled the carburetor the bike started right up. The bike ran perfectly fine throughout the throttle range. Problem occured when you returned to idle. The bike slowly returns to idle. Sometime it just hangs.  It seems to drop to  idle quicker if I blip the throttle. Sometimes it willl hang though at an even higher rpm when I blip it.  It will also return to idle if i lightly tap the body of the carburetor near the throttle valve lightly with a hammer.  I've examined the carburetor while this is occuring and the throttle is closed and resting on the idle screw. No problem with linkage. Could a damaged idle jet cause this? When I think back to how much force I had to use to clean the idle jet I wonder if i actually increased the size of the jet by "boring" through it with the needle. The needle's gauge may have actually have been to big? One other thought. I know i turned the pilot air screw at least a half a turn when removing the bowl but I'm pretty certain I returned it to it's original setting. Could a misadjusted pilot air screw have caused this problem? Could a correctly adusted pilot air screw correct this problem? To this day the bike starts and runs great. The slow to/hanging idle is  so annoying however that I have removed the carb again to try to rectify. I would appreciate your thoughts.  

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It is not a pumper carb.

Replace the pilot jet. You CANNOT ream pilot jets without damaging them

You have 'hanging idle" it's because you idle was set too high before adjusting the fuel screw, or you have an air lead at the fuel screw, air boot, etc.

Edited by TheKoolAidMadeMeSick

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Thanks KoolAid. I'll replace the pilot. On the outside of the carb near where my choke cable hooks there is a visible rod that that has a boot on it. This rod runs vertically from down adjacent to the carb bowl to up toward the middle of the carb. It looks like if you open the throttle up enough part of the throttle linkage makes contact with this rod and presses it down. I looked at what the other end of the rod makes contact with and it is and it is a spring loaded rubber diaphragm. When the rod is pushed gas squirts from a port. j Is this not what is called an accelerator pump? If so is this what distinguishes a non pumper carb from a pumper carb? Thanks again for your help.

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