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2005 kx250f Decompressor moving

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Hello all,

Not sure if this is the proper place to post.

I have a 2005 kx250f with a brand new head from millennium technologies. This means new valves, seats, and springs. I also have a brand new cylinder, piston, and rings. The bike is making a ticking noise that seems to be coming from the head. I checked the valves clearance and it is within specifications. The timing is also correct. 

Here is my question

When I took a look at the exhaust cam, I noticed that the auto decompressor moves around a lot WITHIN the camshaft (So not hitting the camgear but closer to the cam lobes). I know that it is supposed to open and close when I move it with my finger and it does so smoothly,  but I mean that I am able to wobble it around within the groove that it sits in within the cam. Is the auto decompressor supposed to fit snuggly within the hole in the camshaft? When I move the decompressor around it hits the cam and that causes ticking. I just want to know if this movement is normal.

Thank you,

Stephen

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Here is the decompressor. The side furthest from the spring is the side that moves around A LOT. I tried to take pictures of areas that look worn to me but I am not sure if this is the way it is supposed to look. In the photo where you can see the TV in the background, you can clearly see the difference on the piece that is just above my index finger. Should this piece be perfectly round to hold it in place? I know that the very far part is supposed to be uneven to allow the exhaust valve to stay open.

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Interesting.  I do not have a top end opened at the moment to compare.  However, great catch and great question as that sure looks like a lot of excess movement.  I recall being able to turn it but never wobble it like that.  Perhaps there is more to this story.  Why is the head rebuilt?  Perhaps a bushing for the decompressor let loose and went through it?

 

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Head was rebuilt due to a dropped valve. I have ordered a brand new decompressor and will compare it to the one I have now. I will post the difference. Hopefully this can help someone in the future. 

 

I took my bike to the shop and they said the slight ticking noise is normal. Motor runs very strong. The only concern I have is that my pilot screw is turned out 1 1/4 turns out. Is it safe to run this screwed in? I figure this means that the carb is running rich so I have to lean it out with the pilot screw in so far. There is no backfiring or bogging. I know this does not have to do with the topic title.

Thank you for the input!

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Update on the compressor:
The uneven wear patterns are normal. I ordered a brand new decompressor to compare and it is the same.

Update on ticking noise:
Found out it was my intake camshaft. The cam lobe was damaged due to what may be overheating.

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Efff yeah...good for you.

I was born in Miami! Left in '89. My entire family is there still. 

Legal lane splitting and MMJ were icing on the cake. But I moved west for the industry and desert riding, which is my fav.

Best of success to you.

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