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07 CRF250r top/bottom rebuild

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My sons 07 CRF250r bike seized over the weekend so I started tearing into it. Looked like we struck it rich with gold when I pulled the oil filter but that just meant it was gonna cost my $$$$.

Anyways I have the cases split and found that it is the crankshaft bearing so will be doing a complete bottom end rebuild too. My problem is that the cases have scoring in them where the crankshaft sits. Wondering if I could just use some steal wool to clean that up?

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My problem is that the cases have scoring in them where the crankshaft sits. Wondering if I could just use some steal wool to clean that up?

 

Where exactly is the scoring?  Is it where the main bearings are pressed in? 

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Bummed it happened but it happens, rebuilt my crf450r about 6months ago and now have over 45hrs on that top/bottom end. I've done 3 crf450r's since then but this is my first 250.

The scoring isn't were the bearings go, it's were the larger round part of the crank rotates.

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The scoring isn't were the bearings go, it's were the larger round part of the crank rotates.

 

So, the side of the crank (crank web) that sits just off the case.  If so, just clean the score marks up and you should be fine.  :ride:

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It's actually not the side but I guess it would be the outside diameter of the crank web

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Can you post a pic?

photo_zps3fbbd050.jpg

photo_zps98e63b94.jpg

I colored it with sharpie to make it more noticable.

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If they are just scratches, and do not intersect with any sealing surfaces, you should be find. It looks like those scratches occurred when pieces of the bearing got between the crank webs and the cases. It happens. If it has not gone all the way through, or if the scratches do not seem too deep, I would re-run it.

 

If there is any doubt in your mind as to structural integrity being compromised-replace all damaged pieces!

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If they are just scratches, and do not intersect with any sealing surfaces, you should be find. It looks like those scratches occurred when pieces of the bearing got between the crank webs and the cases. It happens. If it has not gone all the way through, or if the scratches do not seem too deep, I would re-run it.

 

If there is any doubt in your mind as to structural integrity being compromised-replace all damaged pieces!

Thanks!! That's kinda what I was thinking. I don't feel there is any problems as they aren't that deep. I guess I will wait for new crank to come in and rotate it in cases after I clean them up to verify that nothing will hit the grooves

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x2 at what Kawabuggy said.  If they are not that deep and don't interfere with the crank you should be fine, just make sure any burrs are flush with the case.

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