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my top end what do u think?keep or new piston

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so i bought this bike at the beginning of the year. the guy said its hardy been ridden and has gone threw 2 owners making me the third. the guy who i bought it off said it has the original piston witch is hard to believe because it has pretty good compression when trying to start it. its a 2003 Honda cr 250.. iv already pulled off the head and it looks alright but there's some build up of the power valve and in the piston head

http://i1206.photobucket.com/albums/bb450/crjunkie/IMG_0145.jpg

http://i1206.photobucket.com/albums/bb450/crjunkie/IMG_0144.jpg

http://i1206.photobucket.com/albums/bb450/crjunkie/IMG_0142.jpg

http://i1206.photobucket.com/albums/bb450/crjunkie/IMG_0141.jpg

im most likely gonna put a new piston, rings, and gasket kit in so tell what you think.

thanks!!!!

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how about taking out and mesuring the piston to see if its in spec?

idn why people think that by someone who knows bikes looking at it, they will know its its good or not.

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yea that would be a good idea. i was just trying to be quick and see what people thought. do you know a good place to find out specks like that because i don't have a service Manuel yet

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wait for your service manual to come in. unless you want to put it together without proper torqu specs and other information.

im sure someone in here knows the numbers.

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I would personally throw in a new piston for peace of mind. I dont trust any seller when they say it has a new or low hour piston/top end.

OEM, Wiseco, ProX are all good pistons. You just have to warm them up good when your out riding before you start ripping around.

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so far it sounds like im gonna finish pulling the jug off tomorrow or today and then go out and buy a ball hone. how do u work one because iv done like 2 top ends and nether of them need to be honed?

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so far it sounds like im gonna finish pulling the jug off tomorrow or today and then go out and buy a ball hone. how do u work one because iv done like 2 top ends and nether of them need to be honed?

I use a brush similar to the one in this auction for plated cylinders. And lots of hot, soapy water.

http://www.ebay.com/itm/2-1-4-Abrasive-Nylon-Deburr-Brush-Tool-Aluminum-Oxide-/230724884332?vxp=mtr&hash=item35b846576c

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what is piston wash?

piston wash is what you see on the top of your piston. the standard is pretty much about a thumbnails total of "wet" areas.

i prefer a forged piston for durability. wiseco has been good to me.

pro x is good too, essentially an cast oem piston. nothing wrong with either piston type, but again, i prefer forged from a durability standpoint.

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cant really tell just by the top of the piston... but just throw in a new piston to be safe. dont want to break the piston skirt

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ya i dont think your standard ballhone is intended for a plated cylinder with ports. let us know how it works out :bonk:

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ya i dont think your standard ballhone is intended for a plated cylinder with ports. let us know how it works out :bonk:

I would agree with this post a did not think you could or should hone a cylinder that has been plated, unless it has been re sleeved. Best bet is to get the specs and manual and do it right within all the tolerances listed. Good luck. Oh, I have seen a lot worse cylinders and pistons than this. If in doubt always replace.

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Like the previous posts said, you gotta take it apart and measure it, but you might as well replace the piston while you have it apart.

OEM piston and gaskets or Wiseco.

Then break it in and enjoy!

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Cheap ins. = New top end & peace of mind. You've gone this far taking it apart. No need for a hone.. if the hone marks are still there just use a scotchbrite with warm soapy water. I've run forged for durability & longevity.

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by the looks of it you have very little cross hatch i would replace the piston and rings get a machine shop to properly measure the bore and get it honed. Yes scotchbrite is ok so ive heard but in my opinon get properly honed with a ball hone so the rings have something to wear agianst during break in.

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