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Hello great people of thumper talk. Well I've been having some problems with my old 2002 YZ250F. I was riding a few days ago when my bike just sputtered to a stop almost like it ran out of gas. Well gas was not the problem and I couldn't get her to run she would only fire for a second then die. I found that one of my TPS wires snapped, so I figured the reason it wasn't running was because of that wire. After soldering it back together it was still doing the same thing, so I just left it for the night. When I came back the next day whilst kicking it over I noticed all of a sudden the kicker stopped. the motor was seized. I tried turning the crankshaft at the flywheel and it would not budge forward at all but it would turn backwards or clockwise, so from here I figure I'll start taking the bike apart and figure out whats locking it up. Once I removed the cylinder head I was at a surprise when I saw this relatively large piece of brass sitting on top of my piston. I was thinking where in the hell did that come from. It was getting too late for me to go any further tonight, so I figured I would post a picture on here to see if anyone can tell me what they think this piece may go to. Is it something in the crank maybe up by the valves, from the carburetor I have no idea. It just amazes me that the piece is so intact since it was sitting on top of my piston. Also after that I did try turning the crank again, and it did turn but it felt horrible. It was very clunky and it sounded like shit might be grinding in there so I stopped. Well thanks for taking a look and if you have any insight as to where that piece might have come from please let me know. Other than that I'll be breakin her down further tomorrow.IMG_2071.thumb.JPG.adf3ca1bde958f124141587332a3d5ed.JPG

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I could be way off but could it possibly be the top of the needle from your carburetor?

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The only place i could think of that comming from would be the carb. Wow amazing that it actually made it past valves? Sorry to see this happen. Subd

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Yea I was thinking maybe something in the carb, just amazed that it would have gotten in there. I will break down the carb tomorrow as well just to make sure nothing has made its way out somehow. I will post more as I discover. Thanks for the replies as well, didn't expect people to respond so quick.

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Definitely looks like the top of the needle where the clip is supposed to seat, but I'm trying to figure out how the heck that made it down the carb, through the intake and past the valves...

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Well sure enough it was the top of the needle in the carb. When I went to take off the screw on top of the slide to take the needle out it was all jacked up. The little brass piece with the spring underneath it was all crooked then I saw the clip sitting there with no needle. Flipped it upside down and here comes the needle with half of the rings gone. I still don't understand how it managed to get all the way into my cylinder. At least now I can rest knowing what caused it, but it is definitely disappointing not having a running YZ anymore. She was a damn good bike too. Well at least I got my KTM 250 XC to ride while I figure out what I'm gonna do with the YZ. Will definitely be getting a newer FI YZ sometime in the near future. They're too good of bikes to not have one around.

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Damn... I'll be trying to figure that one out for awhile... Eady fix, minus the torn off head...

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