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Yz250 standard bore piston replacement

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I'm replacing the piston in my 2005 yz250 and ordered at Wiseco.  Just want to double check that all standard bore Wiseco pistons are the same size and will work....?

My OEM piston was marked A.  Read somewhere where someone was claiming that a Wiseco wouldn't work with a YZ with the A size piston bore.  This has me a little freaked out while I'm in the process of assembling it.  I was told that the difference between A and D OEM pistons was 100 thousants and therefore any standard bore piston from Wiseco would work.  

Any input is appreciated!

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I'm replacing the piston in my 2005 yz250 and ordered at Wiseco.  Just want to double check that all standard bore Wiseco pistons are the same size and will work....?
My OEM piston was marked A.  Read somewhere where someone was claiming that a Wiseco wouldn't work with a YZ with the A size piston bore.  This has me a little freaked out while I'm in the process of assembling it.  I was told that the difference between A and D OEM pistons was 100 thousants and therefore any standard bore piston from Wiseco would work.  
Any input is appreciated!

Hey man I had a B on my head that's a 66.36 & I went with a D 66.38 it's fine no matter what got 2 hours on top end only thing that should matter is that you assembly it correct and you're all good .

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Thanks for the replies.  My local shop says any Wiseco will do so I'm pretty sure it's ok.  Might call Wiseco tomorrow morning just to be sure, but I think I'm being overly cautious as I haven't done this for a lot of years.  

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Thanks for the replies.  My local shop says any Wiseco will do so I'm pretty sure it's ok.  Might call Wiseco tomorrow morning just to be sure, but I think I'm being overly cautious as I haven't done this for a lot of years.  

I went with pro x & you was bro I was it was my first owned dirt bike and my first time ever doing a top end lol but you're fine man

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If your cylinder is in good shape, a Wiseco is a great choice.  Put it together and ride!

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