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Namura pistons hate two strokes

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I buy broken two strokes off Craigslist and fix them up for my family to enjoy. After my fourth purchase with all bad top ends I am starting to see a pattern. All 4 bikes had namura pistons and all four the piston broke and was to blame. I've seen crumpled crowns to crack in half and shattered skirts. Is any one have the same issues or is namura just junk. IMG_1825.JPGIMG_1826.JPG

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Jetting May be involved. Oil mixture ratio or just plain too many hours. Those who skimp on parts due to prices also tend not to maintain items very well too. Disposable Society.

I've had plenty of namura that I installed and ran without failure.

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Very true ratio and jetting is key to a happy 2 stroker.
I can tell you all bikes came from people who probably shouldn't even own a bike because of the lack of tools and the scenario of which they sold the bike in the first place. I am not complaining at all at scoring big on a broken bike. Just wanted other people's opinion on namura pistons.

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Very true ratio and jetting is key to a happy 2 stroker.
I can tell you all bikes came from people who probably shouldn't even own a bike because of the lack of tools and the scenario of which they sold the bike in the first place. I am not complaining at all at scoring big on a broken bike. Just wanted other people's opinion on namura pistons.


For those unable to maintain but do know how to warm a motor up - a forged piston would be much better for them.

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Namaura is built at very modern foundry and machine works, they can build really good stuff or real cheap junk depending on what the middle man orders.  I used them in various rotax applications with good luck, even in 1000cc pro stock motors.  Judging from the forum posts I'm not sure I'd chance it with the bike applications, they seem to be low price point spec.

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A piston with excessive skirt wear can break a piston skirt and have the fragment puncture the crank well. I have seen that twice from POs that run a piston too long because of the cost of replacement or even merely pure ignorance.

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well i have rm80 with Namura piston and rings has about 12 1/2 hours on it and it took a crap on me and lost compression didnt run hot jetting is right.. may be just rings will see tomorrow when i tear it apart  never had this problem with wiseco pistons going out that quick 

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