Namura Piston

[onefasthonda]

Has anyone used a namura piston? Are they any good they are cheapier then most piston's that I have saw?

Thanks for all replies:thumbsup:

[01cr80]

had one in my cr 80 from may to november of last year....not sure how many hours but it was ridden at least 3 times a week for an hour each time....the piston held up good and that bike always had its neck rung out, id use one again as an oem alternative

[ScramblerTom]

I put one in my cr250 and the rings went after a hour - the heat cycles seemed to have taken and I was riding it to a buddies when they just started to lose comp. Not sure if it was my error or the rings - but that's the only experience I've had with them.

[SaLvAgE]

I have been using Namura pistons and gaskets the last couple years. I have not had any problems. Very good OEM replacement piston and a good price. The gaskets are good quality too. ? I will continue to use.

[kawi_wowi]

I put one in my cr250 and the rings went after a hour - the heat cycles seemed to have taken and I was riding it to a buddies when they just started to lose comp. Not sure if it was my error or the rings - but that's the only experience I've had with them.

that sounds like you did not go through the break in cycle but unfortunately i know nothing about these pistons...

[ScramblerTom]

that sounds like you did not go through the break in cycle but unfortunately i know nothing about these pistons...

yes i might be that - I did the usual 5-6 heat cycles and then went on a 20 minute ride around my country block and it seemed fine. but then it died when compression dropped to 65. pouring cold oil in the top end raised comp to 185. I will rebuild the head with the same piston (I have ordered rings from sledpartsguy on ebay and I will be a little more careful with filing my ring gap and my heat cycles. Nothing else looked to have gone bad. To be honest the piston is still on the bike - I just pulled the jug to make sure it was not junked.

[yz fur life]

So would it be a good idea to go with this brand for a piston for a 2000 yz 125 or not? Herd a few good posts but other than that they all sound bad...

[choppertown]

there is only one bad post.....

good pistons. iv put a few in some bikes.

[ScramblerTom]

the worst thing about these pistons are their resale value. You simply can't brag that you put a namura piston in it. but in the end they work about the same. I have heard that it is not how they work but how they die, I have not seen it but they say namuras will make one heck of a mess when they blow, whereas Wiseco will not. That said I had a Wiseco shatter in my cr250 that blew a hole in the bottom of my cases.

[SaLvAgE]

I have heard a couple people complain about them, but at the same time I read about complaints for all piston brands. I have not had any fail on me like that and I've probably used maybe 15-20 of their pistons.

One thing is that Wiseco is a forged piston and 99% of Namura's line is cast. There are differences in expansion and thus break in cycles needed for the 2 types so be sure to figure out what you need to do, but yz fur life I think you will be satisfied. They also have the B & C which can come in very handy (0.01mm larger size piston)

[yz fur life]

I didn't have good luck with this piston. What happend was I changed my piston and I did all of the warmups (break ins) and I was out riding it and it just lost compression. It ended up scoring my cylinder on the exhaust side and melted the ring to the piston. Hopefuly I can get it fixed soon!

[terrobelone]

F@#k that!!!

[MX926]

I used namura pistons for the 2010 season in my 04 cr250, with great luck. Very pleased with the way they hold up, and a great value as well.

[terrobelone]

pistonS!! how many and how long do they last assuming you race them 10-15hrs?