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My first time rebuilding a 2010 crf250r bottom end

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Hi Guys,

I have recently found a chunk of brass metal in my oil filter and have determined it is time for a bottom end rebuild. I have read through the service manual and was wondering what tools are absolutely necessary to purchase and which ones can I get by without having to have. Any help would be greatly appreciated.

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A flywheel puller is a necessity, as is a small gear puller - if the drive gear on the right side of the engine doesn't come off easily. A clutch holder tool, or an impact wrench to remove the clutch inner basket nut makes the job easier - and reduces the risk of breaking the clutch outer basket.

Replacing bearings is much easier done with a hydraulic press, but you can use a hammer and various size sockets (big ones) to bang out/in the bearings. The socket diameters need to match up with the outer bearing races, not the inner ones.

I also keep a few blocks of styrofoam to stick the right, left and center crankcase bolts in, just to keep them in the correct order - There are about 4 different lengths and it is critical to reinstall them in the same locations.

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Here's a good tip from Charlie C on removing and installing bearings.

A trick to removing the bearings, throw the cases in the over at about 400 degrees. They fall right out. Replace the bearings when the cases are still hot. Some actually throw the new bearings in the freezer. Once the new bearings are in, let the cases cool. No stress on the bearings doing it like this.

You can probably get some good tips from this thread I came across a few weeks ago.

http://www.thumpertalk.com/forum/showthread.php?t=1014710

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