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1997 xr250 cylinder head main bearing

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I just bought a project xr250 off a guy. It is about 85% restored. Rocker and Sub Rocker arms are shot, camshaft is shot, and the main bearing on the cylinder head looks rough. I brought it to a local shop, which i dont know much about, and they said it was trashed. They also told me that the cylinder head and cylinder head cover was a matched set. I would have to buy both. I then called a honda dealer and they said I COULD interchange heads and covers. "Any opinions on that issue". My main question is if there is any way to repair the main bearing on the cylinder head, or a place to find a cheap replacement. I would appreciate any help or comments fellas.

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Can you post a photo? If the damage is not too bad off, it can be lived with.

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Thanks. Ill see what I can do about a pic. Im new to this, I appreciate the reply. Have you ever heard of machining out the old bearing and installing some kind of a new bearing or is that even practical in your opinion

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Honda sells the head and cover as a set because the bearing bores are machined with the two parts assembled. Mixing parts is possible but will very likely result is mis alignment and a change in bore diameters resulting in too much bearing clearance and/or binding.

Welding to build up the bearing surface is not an option because the head is pressure cast which entrains hydrogen gas. Welding releases this gas creating porosity in the weld.

The bearing bores could be machined to accept bushings, the XR200 uses a bushing on the end of the cam that is pin located into the head.

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Thanks for the info. Is there a bushing made for that application? I have a friend that can machine out the bearing, if there is a bushing made for the XR250 main bearing. As of right now I am open to an suggestions as I really dont want to go spend $400 on another cylinder head. Thanks again.

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I have a basher of a xr100 we picked up cheap, the oil filter gauze in the bottom was blocked with cam chain tensioner debree, which restricted the oil to the cam.

I tapped and screwed brass screws onto the worn area and with patients and time used a die grinder and file set to bring it back to size. The cam now fits and runs well, the bike doesn't stop.

Go the xr !!

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