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I have a 2002 cr250 2 stroke that recently blew up. i believe it was due to low octane fuel and extended periods of holding it wide open.

Mill tech already replated my cylinder, redid the power valves, and sent me a new piston with gaskets but i was wondering if i can reuse this cylinder head if i really clean it up.

Any advice would be appreciated. I can buy a new cylinder head for about $85 if needed. i would like to reuse this one but i already have $600 into the top end by sending it to millennium and the parts alone so i suppose another $80 wouldn't be too bad.

pic of cylinder head attached.

cylinder head.JPG

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I won't tell you what to do, but I will tell you I have used a head like that before.

I wasn't too concerned with the indents, but I set down and slowly sanded any sharp edges, high spots, and removed any embedded metal so as not to have any thin areas that could heat up and cause detonation.

If the deformity had an effect on band squish, fuel swirl and flame travel, I couldn't tell; but I used race fuel and 927.

Ultimately, I would install a new head.

Edited by WALKINGWOUNDED
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I would send it to a machine shop and have them handle it; they'll be able to do the best work.

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You should be able to get it re cut for fairly cheap. You could also use it to measure and correct squish if need be.

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From looks of it I hope you did bottom end also lol :goofy: other then that some 380 sand paper and peice of glass and lightly sand a bit. Will work, or just buy new one:thumbsup: 

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I agree-DO NOT run that run head! The raised metal areas can, and will, become areas of super-hot pre-ignition.

You already know to just buy a new head. It's not worth messing with something that could potentially cost you so much more money down the line. $85 now, or an entire motor rebuild soon? Easy answer.

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Hell, even a used one that hasn't been modified would be better and prolly only 40$. Heads don't really wear out. Avoid one that has been cut to adjust squish volume because each volume is specific to that bike.

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