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cr250 piston rings wont come off piston

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I have a cr250 and am planning on putting new rings in it and i was able to get one of the 2 rings on the piston off but the other one seems like it is stuck on there and it wont come off. I tried cleaning it with degreaser and oven cleaner and then took a pick to it but it still wont come off. An suggestions on how to get it off to replace it or am i going to have to get a new piston? 

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Why would you want to reuse the old piston? A top end job is rings/piston/piston bearing/pin and gaskets. The old piston  is  junk, I don't know anyone who would reuse an old piston. Do you really want to risk breaking a piston and really screwing up the motor over $100 or so?

 

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Why would you want to reuse the old piston? A top end job is rings/piston/piston bearing/pin and gaskets. The old piston  is  junk, I don't know anyone who would reuse an old piston. Do you really want to risk breaking a piston and really screwing up the motor over $100 or so?
 

People just do a ring job all the time man
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People just do a ring job all the time man

[emoji23] seems like you wouldn’t even have to post to get a good answer. You’d think if the rings don’t come off it’s time for a new piston and also just why not replace the piston? Never really heard of any long lasting motor that people just replace the rings on… Only time I’d deem a ring replacement okay is if I had to pull of the cylinder at like 7 hours and just did the rings while I was in there.

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1 hour ago, HRC27 said:

Not when one of the rings are stuck in the piston.

This is correct ...unless you're in some kind of pinch and feel the need to squeeze some more time out of that piston.

stuck ring means show-stopper if planning to re-ring a piston.    Detonation or near seizure is usually what causes it ....very very seldom does oil do that.

If you did a compression test, saw low compression and tore it down to find the problem , guess what, you found it.

 

Edited by ss-racing

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I have a cr250 and am planning on putting new rings in it and i was able to get one of the 2 rings on the piston off but the other one seems like it is stuck on there and it wont come off. I tried cleaning it with degreaser and oven cleaner and then took a pick to it but it still wont come off. An suggestions on how to get it off to replace it or am i going to have to get a new piston? 
How's the cross hatching on the cylinder wall? Don't even consider not doing the whole top end. Wiseco piston and OEM gaskets. Saving $60 on a cheap kit will burn you in the end.

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How's the cross hatching on the cylinder wall? Don't even consider not doing the whole top end. Wiseco piston and OEM gaskets. Saving $60 on a cheap kit will burn you in the end.

The cylinder could use a hone, there is no chips or scratches. Where is a good place to take it to get a hone job?

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First I would measure the bore before you buy anything. Harbour Frieght sells bore measuring tools real cheap. Pick up a cheap micromator as well. $20 total. I just went through US Chrome and was happy with the results. I went all out and had mine stripped, plated, and honed back to OEM 66.4mm. If you go that route pick up a Wiseco kit and send them the cylinder and piston only. No rings needed for fitment. You can buy a hone ball, but I've heard horror stories because people overdo it.

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1 hour ago, Fred29 said:

You can buy a hone ball, but I've heard horror stories because people overdo it.

yup, at one point i thought i could strait stone drill hone a worn stock steel bore out to a used first overbore piston... totally ruined it..

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