250 Rebuilding KX250

i am going to rebuild my 03 kx250 motor. I want to tear the whole motor down, replace the top end and check out the bottom end. Replacing parts as needed. I have never torn an engine all the way down so any comments or advice would be great!
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Without a doubt replace all the bearings and circlips in the trans. Inspect all of your bushings and spacers for unusual wear. Then mic them. Look for warn hear dogs.
 
Yank it, spank it, get the manual... Replace crank bearings for sure. Check trans bearing but most of the time they are fine. Replace all the seals and gaskets. Go get it!!
 
I am somewhere in the middle on transmission bearings. You can test a bearing and since the ones in your transmission live in oil they usually hold up pretty good. all my two strokes pretty much get atf from the time they arrive with me and the only bearing that I seem to have a problem with are the countershaft bearings and then only when they get to me, or if a seal fails and it gets dirt in it. most of the ones that need replacement are probably from being subjected to a chain that was too tight. anyway, when i get in one for the first time that is the one I almost always replace, and much of the time it is just to make me feel better. So far I have yet to find a really bad bearing on the "dead" end of any shaft and that includes large 8-18 speed eaton/fuller transmissions.
 
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Pulled the cylinder head, reed cage, piston and clutch plates. Thought it didn't look to bad and then I pulled off the KIPS cover and saw where all the carbon build up went, dirty!
 
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