How Good Is A Namura Piston

[sweet t-rex 400]

I was wondering how good a namura piston is. Never heard of it and would like to get some reviews. I need to rebuild soon and was looking at pistons on e-bay and seen them on there...a lot of them. Its looks like a lot of people buy them but never could find a review. Any info would be great.

[crownandmonster]

If you ask me I would never buy one. I'm sure many people have used them and had perfect luck, but as far as the powersports world goes I wouldn't but anything but JE or Wiseco.

[400exrip]

Originally posted by crownandmonster
If you ask me I would never buy one. I'm sure many people have used them and had perfect luck, but as far as the powersports world goes I wouldn't but anything but JE or Wiseco.

Yup, Always remember when you are building a motor never throw it together with cheap parts. Go Ahead and spend the extra money and build it right.

Not putting Namura down or anything, But Wiseco and JE have had more time ''under the hood'' than any other companies out there.

[finsteratv]

i've heard of them being "ok" but nothng great but nothing horrible. JE, wiesco or pro-x gets my vote. Pro-x makes the 2 stroke pistons for honda(ART) im not sure about 4 stroke though.

[01boneless]

je or wiseco namarua is junk!! pro x is great in 2 smokers but they are no good in 4strokes :P

[kickindirt57f]

used them in 2 2 strokes ive rebuilt ran good but not in 4 stroke

[2muchquad]

just about anything these days will be fine for non racing.regardless of maker installation is everything.I have personally used them in my banshee and never had a problem.I have seen people use wisecos in a bike and end up shattering them because of excessive piston clearance in cylinder.No piston will hold up if its time for a bore job and people are to cheap to get it done.Bore will only last so long;)

[sweet t-rex 400]

im not racing it but do ride hard and want something that will last but dont wanna pay too much for rebuild. Anybody run them in a four stroke before. I see two strokes but no 4's.

[beastlywarrior]

Their good for an oem replacement their cast just like the stocker so no performance advantage or quality of je or wiseco

[powerbomb400]

We put one in my RMX250 but it is a play around the house bike . I've heard good comments and bad. I believe I'd stick to a good name brand like a Wiseco or a JE if you are going to ride it alot. I put a Wiseco in my 400ex. I ride it all the time so I was leary about putting a Namura in it cause of some of the reviews I had read.

[01boneless]

just bite the bullet and buy the wiseco there only 125 on ebay the namarua will fail imho

[sweet t-rex 400]

im buying the wiseco for sure. Now the question is should i bore it out some. What is better a 416 or 426 or 440? If im doing this im gonna go all out,might as well right.

[2muchquad]

just go with the 416,save yourself some future bores.not much difference between the 426 powerwise.get the 11 to 1 compression piston you should be golden

[CJM]

Namura is JUNK. I know this b/c 3 hours ride time on my friends banshee and it literally melted. We changed nothing but slightly upping the bore size and uses wiseco pistons and it had no issues on the rebuild.

The cheapest piston I will buy is a wiseco, never had an issue with them either.

Powerwise a 416 and 426 is very small, compression is power-not bore size. Id do the 416 only b/c if you need to bore it again (and you will sooner or later) you can bore to 426, you do 426 you either need a new stock sleeve or a 440 sleeve should you need to bore it again.

[CDCHONDAS]

Originally posted by CJM
Namura is JUNK. I know this b/c 3 hours ride time on my friends banshee and it literally melted. We changed nothing but slightly upping the bore size and uses wiseco pistons and it had no issues on the rebuild.

The cheapest piston I will buy is a wiseco, never had an issue with them either.

Powerwise a 416 and 426 is very small, compression is power-not bore size. Id do the 416 only b/c if you need to bore it again (and you will sooner or later) you can bore to 426, you do 426 you either need a new stock sleeve or a 440 sleeve should you need to bore it again.


There are a lot of variables that you likely don't know. I can tell you that the piston melting was not its fault but likely a lean condition. Was the crankcase pressure tested when assembled? Could have had an air leak. Perhaps the alloy has a slightly lower melting point than the wiseco, but one way or another that bike was or is running lean. I use namuras and sometimes I feel like I should be ashamed using such a cheap piston but I've never had an issue with one either and I've been through my fair share.

[2muchquad]

There are a lot of variables that you likely don't know. I can tell you that the piston melting was not its fault but likely a lean condition. Was the crankcase pressure tested when assembled? Could have had an air leak. Perhaps the alloy has a slightly lower melting point than the wiseco, but one way or another that bike was or is running lean. I use namuras and sometimes I feel like I should be ashamed using such a cheap piston but I've never had an issue with one either and I've been through my fair share.



Agreed;)

[hocman123]

disagree

i know that bike cjm was talking about and it last a bit longer then 3 hours i would say 5-8 hours before it stopped and all he did was get the same bore in wiseco cleaned up the cylinder a bit and never changed the carb jets. and i also know he jetted it a bit rich to the point were he has to rejet or adjust his needle if he wants to ride his banshee in the winter b/c it would bog in 30 temps.

for the peace of mind it really is only 20-30 bucks more for a wiseco piston set on ebay its really not a bank breaker

[CJM]

^ Exactly. The guy who assembled the banshee I mention with the namura piston knows extremely well what hes doing too. Bike was assembled, ran ok, had maybe 3-5 hours (we didnt get 8 it locked up) and it just locked. Opened it up and bingo it was melted and the rings took a dive out the exhaust. Thank god it wasnt a 4 stroke or it woulda been worse.

Its not the first time Ive heard of namura being junk either, they are cheap for a reason...

[trxPOWER]

i have absolutly ZERO problems with my big bore piston and gasket kit from them. i like all the people who have never had any experience with them, but still have negative things to say about them. welcome to the internet.

[CJM]

Originally posted by trxPOWER
i have absolutly ZERO problems with my big bore piston and gasket kit from them. i like all the people who have never had any experience with them, but still have negative things to say about them. welcome to the internet.

Everyones entitled to thier opinions, but NEVER have I or anyone I know had a problem with wiseco..plenty have had issues with namura.

[01boneless]

this ^^^ if there set on namura well fine! but wiseco JE or cp is way better . how many problems have you seen on this thread from wiseco? none how many from namura at least 2. thats enough there for me to make my choice