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Anyone have a link to the page that shows pictures of differnt symptons of engine malfunction by looking at the piston? I put new fmf pipes on my bike and i took a peak at the piston through the exhaust port and noticed a burn spot below the rings..and im pretty sure that means somethings wrong..like blow by, which im guessing is bad rings? the bike still runs good and starts relatively easy, but im concerned about the crown of the piston breaking or something

its a 01 cr250 btw

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thanks, i guess i have slight blow by but it isnt nearly as bad as whats shown on gorrs page..hmm

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it isnt nearly as bad as whats shown on gorrs page..hmm
If it's time for a top end, Eric suggests going with a Wiseco piston as there have been problems with the ring locating pin coming loose on the OEM pistons. I used one and it seems like a good piston.

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If it's time for a top end, Eric suggests going with a Wiseco piston as there have been problems with the ring locating pin coming loose on the OEM pistons. I used one and it seems like a good piston.

to piggyback a bit on what skip said, the stock honda pistons on the 92-01 motors also tend to develop a crack on the intake skirt when the rings have been run too long.that can happen anywhere from 5 hours up to and over 100 hours...it just depends on how hard its been run. the wiseco piston pretty much cures the cracking, but the ring life would be about the same. the forged piston is the way to go IMO:thumbsup:

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the forged piston is the way to go IMO:thumbsup:
I agree. I think the only down side I've heard of with the forged piston is cold seizures when people ride before the engine is fully warmed. That could be an issue in NJ.

From my drag racing days, I really didn't have a good opinion of Wiseco; there are just so many better piston brands for that application. But for the CR, the Wiseco looked pretty nice. Piston to cylinder clearance was 0.0014" and both ring gaps were spot on at 0.013". Hard to beat for the price.

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yea ive always used wiseco stuff in my bikes..from my 80 to 125

i guess in a week or so ill be buying a new piston

skip its hot now in nj so the cold-seizue problem shouldnt be too much of a problem, however i always warm my bikes up before i ride them

im not sure if it really needs a top end but i thik i might do it anyway just to make sure, it just seems like its alittle bit burnt under the ring but its a brown color and not so much black..

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I bought a brand new 01 CR250 and earlier this year bought another. Great bike and the Wiseco does a great job, just make sure you warm the bike up before you hammer on it.

I am probably not the best to go by with changing top ends because I almost always put a new top end in once per year. I race moto 4-6 times a year and just ride other than that. The top ends come out looking VERY good, in fact, I could probably just get by with changing rings, but since I am in there already, I just do the whole thing.

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Sounds like a good time to poke around and see what's going on inside. If you get time, post the ring gap info on the old rings when you get them out. Could be an interesting data point.

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