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Opinions on Piston

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Just wanted to get a few people's opinion on my piston. This is a Wiseco pro-lite after 80 hrs. pretty hard MX. Bike is a 1999 kx250 and was running fine, I just replaced the piston because I figured 80 hrs. was starting to push my luck.

Does it tell you anything?

1e6e3.jpg

1aa10.jpg

b12ca.jpg

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80 hrs on hard mx,you were really pushing your luck.I guess your putting a wiseco back in there.

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^ yes, fresh wiseco piston and rings and fresh cometic gaskets are now installed and she's running like a champ! I just wanted to see if anyone had any insight into what my old piston is "telling" me, if anything, about my running conditions.

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did you he 80hrs on the rings also, Im at 70hrs on piston and 30hrs on rings, will be changing at 80 as well. Piston looks fine maybe a little rich, no wear marks that I saw.

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From the pics, I see jetting that's pretty close, rings that are worn out, no signs of detonation or dirt ingestion, very shiny skirts indicating the piston is done, and pretty reasonable blow-by for the hours and worn rings.

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did you he 80hrs on the rings also, Im at 70hrs on piston and 30hrs on rings, will be changing at 80 as well. Piston looks fine maybe a little rich, no wear marks that I saw.

yes, 80 hrs. on piston and rings (i always replace them both at the same time). thanks for your insight, better to be on the rich side rather than lean :smirk:

From the pics, I see jetting that's pretty close, rings that are worn out, no signs of detonation or dirt ingestion, very shiny skirts indicating the piston is done, and pretty reasonable blow-by for the hours and worn rings.

THIS is what i was looking for, thank you!! :bonk::lol: how are you able to tell that the rings are worn?

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yes, 80 hrs. on piston and rings (i always replace them both at the same time). thanks for your insight, better to be on the rich side rather than lean :smirk:

THIS is what i was looking for, thank you!! :bonk::lol: how are you able to tell that the rings are worn?

The edges look sharp. If you look at new rings, they are beveled.

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how are you able to tell that the rings are worn?

My guess would be the blow-by.

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The edges look sharp. If you look at new rings, they are beveled.

ah, i c. thanks

My guess would be the blow-by.

blow-by could be one indicator, but blow-by could also be blamed on a worn cylinder from what i understand. i was asking how he could tell from looking at the rings alone, not by proxy of something else.

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In the third picture, that piston has no rings, am I right?

I can't see how you can tell that the rings have sharp edges in the first two pictures.

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In the third picture, that piston has no rings, am I right?

I can't see how you can tell that the rings have sharp edges in the first two pictures.

In forty years of riding I've seen a lot of rings.

I also know how to zoom...:smirk:

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