brand new piston snapped chunk off

cadeclarey
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cadeclarey
Edited Date/Time 8/1/2021 5:02am
I am a 15 year old that does all my bike work by myself because my dad isn’t around too much and have done top end and motor work countless times so it’s not like i’m inexperienced but I have never seen this happen before, so basically my brand new vertex piston going in my race bike snapped a chunk off right by the ring gap on the first start, idk why this would happen and am wondering. I have a race this weekend and we are rushing to get parts and get the bike together and can’t sacrifice it doing this again.
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DynoDan22
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DynoDan22 7/23/2021 3:27pm
7/23/2021 3:27pm Edited Date/Time 7/23/2021 3:28pm
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as well.
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cadeclarey88
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cadeclarey88 7/23/2021 3:34pm
7/23/2021 3:34pm
DynoDan22 wrote:
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as...
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as well.
I am a complete moron, i’m sorry for posting this I didn’t even look at the picture, i don’t know what i’m going to tell my dad. i’m a little scared of what he’s gonna think. my moms getting a new piston hopefully he won’t look at the picture and notice it’s in backwards, i’m a little scared of what he’s gonna say.
cadeclarey88
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cadeclarey88 7/23/2021 3:36pm
7/23/2021 3:36pm
DynoDan22 wrote:
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as...
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as well.
the cylinder still looks good, i’m grateful for that and the head is perfect aswell. again i’m sorry for posting this i should’ve been able to notice this on my own.
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kijen
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kijen 7/23/2021 3:44pm
7/23/2021 3:44pm
Yep dont beat your self up, grown men have done worseSmile just learn from it, maybe a checklist as you go....im in aviation maintenance and many mistakes are made by people with twenty years experience, usually traced to complacency.
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willbilly
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willbilly 7/23/2021 4:51pm
7/23/2021 4:51pm
Haha! You sound like me about 50 years ago. You made a mistake. No big deal. I’m impressed that you work on your own bike and admit your mistake. You sound like a responsible young man. Hope you get it fixed soon.
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NITRODOG
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NITRODOG 7/23/2021 4:55pm
7/23/2021 4:55pm
Fix it and Rip it! Learning to take care of your own bike will pay off in spades later on! This will make great bench racing material for you later on!
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pete24
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pete24 7/23/2021 5:00pm
7/23/2021 5:00pm Edited Date/Time 7/23/2021 5:01pm
ive been known to take a head off here and there to make sure the piston is in the rite way,,,,,,,,,,,,ask me why
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DynoDan22
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DynoDan22 7/23/2021 5:15pm
7/23/2021 5:15pm
What ever you do, clean the bottom end out and make sure you get every piece of debris out. Flush the bottoms end out with premix gas and try to get all the little pieces out. Good luck!
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captmoto
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captmoto 7/23/2021 5:41pm
7/23/2021 5:41pm
A good friend of mine bought the 92 Peak CR250 that Pro Circuit built for Jeremy McGrath to run some East Coast SX races on. Maybe 4 rides on it. After riding it for a year he decided to rebuild the top end and did the same thing. he bought a new cylinder and asked PC to port it like the did for Jeremy. I think they had something else in mind and it never ran the same. It ran great but not the same powerband MC used.
Like someone else said, don't beat yourself up. Props to you for doing your own REAL work on your motors.
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cadeclarey
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cadeclarey 7/23/2021 8:34pm
7/23/2021 8:34pm
cadeclarey wrote:
I am a 15 year old that does all my bike work by myself because my dad isn’t around too much and have done top end...
I am a 15 year old that does all my bike work by myself because my dad isn’t around too much and have done top end and motor work countless times so it’s not like i’m inexperienced but I have never seen this happen before, so basically my brand new vertex piston going in my race bike snapped a chunk off right by the ring gap on the first start, idk why this would happen and am wondering. I have a race this weekend and we are rushing to get parts and get the bike together and can’t sacrifice it doing this again.
UPDATE, my mom brought the piston home, got it all sorted out, didn’t get yelled at and the bike is running great and hopefully i’ll be able to go 1-1 tomorrow for the overall win!
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cadeclarey
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cadeclarey 7/23/2021 8:36pm
7/23/2021 8:36pm
DynoDan22 wrote:
What ever you do, clean the bottom end out and make sure you get every piece of debris out. Flush the bottoms end out with premix...
What ever you do, clean the bottom end out and make sure you get every piece of debris out. Flush the bottoms end out with premix gas and try to get all the little pieces out. Good luck!
drained the oil and it was good with no flakes in it, flushed it twice just to be safe👍🏻
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Bearuno
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Bearuno 7/24/2021 5:11am
7/24/2021 5:11am
DynoDan22 wrote:
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as...
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as well.
cadeclarey88 wrote:
the cylinder still looks good, i’m grateful for that and the head is perfect aswell. again i’m sorry for posting this i should’ve been able to...
the cylinder still looks good, i’m grateful for that and the head is perfect aswell. again i’m sorry for posting this i should’ve been able to notice this on my own.
You learn from your mistakes, young man. I certainly did. And, even at a (Great) Grandads age, I'm wary of making mistakes, still.

At least you're doing things for yourself.

Keep your chin up!
GoggleFiend904 7/24/2021 7:22am
7/24/2021 7:22am
DynoDan22 wrote:
What ever you do, clean the bottom end out and make sure you get every piece of debris out. Flush the bottoms end out with premix...
What ever you do, clean the bottom end out and make sure you get every piece of debris out. Flush the bottoms end out with premix gas and try to get all the little pieces out. Good luck!
cadeclarey wrote:
drained the oil and it was good with no flakes in it, flushed it twice just to be safe👍🏻
Gear oil and crankcase are separate on a 2 stroke. If it runs good I wouldn’t worry about it now, the pieces probably flew out of the exhaust when it first happened
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Austin_Rankin 7/24/2021 8:20am
7/24/2021 8:20am
Your doing good this was a learning experience, learn from it and move on.
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Layton
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Layton 7/26/2021 6:45am
7/26/2021 6:45am
I’m confused.

You say that’s a brand new piston but that piston in the picture has been run quite a while.

Did I miss something??
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40acres
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40acres 7/26/2021 6:02pm
7/26/2021 6:02pm
Layton wrote:
I’m confused.

You say that’s a brand new piston but that piston in the picture has been run quite a while.

Did I miss something??
I'm not sure splitting hairs here really adds much value to the overall conversation. Looks like he got it sorted in the end.
Falcon
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Falcon 7/27/2021 10:17am
7/27/2021 10:17am
It's too late now that you have re-assembled your cylinder, but I was going to remind you to check your bottom end bearing for wear. Your rod should not have any up-down play. Side to side is OK to a small degree, but up/down is a no no.
How did the race go?

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ricky racer
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ricky racer 7/27/2021 3:49pm
7/27/2021 3:49pm
DynoDan22 wrote:
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as...
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as well.
cadeclarey88 wrote:
I am a complete moron, i’m sorry for posting this I didn’t even look at the picture, i don’t know what i’m going to tell my...
I am a complete moron, i’m sorry for posting this I didn’t even look at the picture, i don’t know what i’m going to tell my dad. i’m a little scared of what he’s gonna think. my moms getting a new piston hopefully he won’t look at the picture and notice it’s in backwards, i’m a little scared of what he’s gonna say.
Your dad should be proud he has a son that is willing and able to perform his own work on equipment. I know I would be. Everyone makes mistakes. Good on you!!
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LKHill
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LKHill 7/28/2021 5:54am
7/28/2021 5:54am
Layton wrote:
I’m confused.

You say that’s a brand new piston but that piston in the picture has been run quite a while.

Did I miss something??
Yes you did.
Layton
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Layton 7/28/2021 2:41pm
7/28/2021 2:41pm
I think the only thing I missed out on is that he comes on here and claims his piston was brand new and the corner broke off.

Obviously that is not a brand new piston. In fact it’s not even close to new with all the scraped off carbon on it.

Some of you think it’s ok to not tell the actual facts but how is he supposed to get real help when he doesn’t tell what really happened?

Maybe it turned out ok this time but one of these days it will bite him in the ass.
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40acres
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40acres 7/28/2021 3:22pm
7/28/2021 3:22pm
Layton wrote:
I think the only thing I missed out on is that he comes on here and claims his piston was brand new and the corner broke...
I think the only thing I missed out on is that he comes on here and claims his piston was brand new and the corner broke off.

Obviously that is not a brand new piston. In fact it’s not even close to new with all the scraped off carbon on it.

Some of you think it’s ok to not tell the actual facts but how is he supposed to get real help when he doesn’t tell what really happened?

Maybe it turned out ok this time but one of these days it will bite him in the ass.
You didn't miss... you just assumed he scraped off carbon from his piston dome. There are no scrub or scrap marks on that piston dome and it actually looks like its got only a few hours on it if that.

He did get "real" help when someone suggested that his piston was in backwards. None of what your talking about has anything to do with his piston being installed backwards. Take your inspector gadget shit to another thread boss, this one is handled.
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LKHill
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LKHill 7/28/2021 5:33pm
7/28/2021 5:33pm
Layton wrote:
I think the only thing I missed out on is that he comes on here and claims his piston was brand new and the corner broke...
I think the only thing I missed out on is that he comes on here and claims his piston was brand new and the corner broke off.

Obviously that is not a brand new piston. In fact it’s not even close to new with all the scraped off carbon on it.

Some of you think it’s ok to not tell the actual facts but how is he supposed to get real help when he doesn’t tell what really happened?

Maybe it turned out ok this time but one of these days it will bite him in the ass.
Pistons are round and don't have corners...

Honda tried that.
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cadeclarey
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cadeclarey 7/29/2021 10:41am
7/29/2021 10:41am
Layton wrote:
I’m confused.

You say that’s a brand new piston but that piston in the picture has been run quite a while.

Did I miss something??
ran for about 30 seconds lol
cadeclarey
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cadeclarey 7/29/2021 10:42am
7/29/2021 10:42am
Layton wrote:
I think the only thing I missed out on is that he comes on here and claims his piston was brand new and the corner broke...
I think the only thing I missed out on is that he comes on here and claims his piston was brand new and the corner broke off.

Obviously that is not a brand new piston. In fact it’s not even close to new with all the scraped off carbon on it.

Some of you think it’s ok to not tell the actual facts but how is he supposed to get real help when he doesn’t tell what really happened?

Maybe it turned out ok this time but one of these days it will bite him in the ass.
LKHill wrote:
Pistons are round and don't have corners...

Honda tried that.
it was brand new and had ran for about 30 seconds, and all that “carbon” on top isn’t carbon it’s oil.
GoggleFiend904 7/30/2021 9:47am
7/30/2021 9:47am
You quoted the OP with your insult.. how was it not directed at him? The OP is the kid you are talking shit to FYI
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Yeti831
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Yeti831 7/30/2021 9:42pm
7/30/2021 9:42pm
DynoDan22 wrote:
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as...
you installed the piston backwards and the ring ends caught the exhaust port and ripped the crown off. I'm sure the cylinder took a beating as well.
cadeclarey88 wrote:
I am a complete moron, i’m sorry for posting this I didn’t even look at the picture, i don’t know what i’m going to tell my...
I am a complete moron, i’m sorry for posting this I didn’t even look at the picture, i don’t know what i’m going to tell my dad. i’m a little scared of what he’s gonna think. my moms getting a new piston hopefully he won’t look at the picture and notice it’s in backwards, i’m a little scared of what he’s gonna say.
We’ve all done it once. Take it as a learning experience and drive on 🙂

Pro tip: most pistons have an arrow or marker on the crown, this typically goes on the exhaust side 👍

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