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I was riding my 2005 RM125 dirt bike the other day when it bogged down all of a sudden. I noticed the spark plug had backed out of the head, thus causing the stall. I pulled the spark plug all the way out and realized that the small bottom piece of the plug was missing. enter image description here

Evidently it had broken off inside the cylinder. I got the bike home and fished around in the spark plug hole with a magnet to try and retrieve the piece, but I couldn't find it. I even took the head off and fished around some more. I'm about to give up. Is it safe to crank the bike without making sure I find the little piece, or should I make sure and find it before riding again? I just don't want it to cause serious damage inside the engine.

dlu
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hgwhittle
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1 Answers1

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Either it's in there or it isn't. If you've taken the head off, you should see the top of the piston and know if it is there or not. You don't want to refire the thing without knowing if it is there or not. If it is in the cylinder it could rub on the side of the cylinder wall and cause damage. Scoring of the wall and damage to the piston are the two big issues here. I have seen a lot of times where small debris like this will get blown right out of the exhaust. Depending on whether the RM is a two stroke (they were when I was familiar with them) will probably make a difference.

Pᴀᴜʟsᴛᴇʀ2
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