Namura piston

[Tharrell]

Got a replacement Namura piston in and it's not like the OEM model.
It's got higher intake windows, reinforced crown, and a place milled on the exhaust side of the crown that advances the exhaust.
Anybody ever seen one or used one before?
We cleaned up the ports on the cylinder and after bead blasting, will install.
This thing looks like it will not have very much bottom end but will probably scream.
My buddy Sam told me the old Bultaco guys would have pistons like this for top end flat track racing.

 

[super noober]

not a fan of cast namura pistons..... some have had ok luck, some builders have a collection of blown up ones. good luck dude

 

[200+cc]

just had my cyl done too. got namura piston back with head. putting back together today.. see what happens i guess

 

[super noober]

why is namura so popular today lol??? for the extra $15 bucks to get a quality FORGED wiseco i just dont understand

 

[200+cc]

probably cuz they look cool and theyre inexpensive. thinkin really need to keep an eye on jetting. pain in ass where i live, especially this time of year. can be 50 degrees 1 day and 12 the next. anyony from northern states knows what i mean. not really a good time of year to break in a 2 stroke atv. cant help the itch though.

 

[200+cc]

broke in motor. retourqued cyl. and head a couple of times during break in prociedure. mixed petrolium based lube with gas a thick 24:1 and kept close eye on plug. time to run synthetic in it. so far so good i guess....I:I... see how well it takes it the spring/ summer when i can really give it hell.. its useless in the snow even with 300 screws in rear tires and larger sprockets

 

[Blasterdude27]

Did you make SURE its for a blaster? Namura's are coated on the intake and exhaust port sides but otherwise are exactly the same as stock.


Heres what mine looked like when new.

 

[blasterbogger]

i like wiseco pro-lite its what im running,i was going to buy a namura until someone here on the forum told me that they dont tend to hold up as much as wiseco and they tend to blow up

 

[scotj77]

that sound's more like one of the vito's super stock pistons to me

 

[Jay]

namura performance piston i think that what they called it i have seen one of them before

 

[Blasterdude27]

that sound's more like one of the vito's super stock pistons to me

X2. Doesn't sound like a namura to me.

 

[Budget_Blaster]

Nothing wrong with namura.they're who makes your oem stuff to begin with.I highly doubt contrary to popular belief that the factory would invest in a sh*tty manufacturer to make something as important as a piston.


Just put a namura in my brothers RM250 has the coating as in the pics and runs like a raped ape!

 

[super noober]

Nothing wrong with namura.they're who makes your oem stuff to begin with.I highly doubt contrary to popular belief that the factory would invest in a sh*tty manufacturer to make something as important as a piston.


Just put a namura in my brothers RM250 has the coating as in the pics and runs like a raped ape!

huh, i could have sworn it was pro x yamaha used as oem not namura.

 

[royalt67]

huh, i could have sworn it was pro x yamaha used as oem not namura.

I believe you are correct. Namura is actually a fairly new manufacturer (10 years?) but I think they are OEM on some bikes.

FWIW, I just tore my motor down and the Namura piston looks great. The cool coating is gone, but that is just for break-in anyway. This is with one season of racing on it. Contrast that to my last Wiseco (one season) that came out of the motor with cracks in the piston skirt.

And bear in mind, Namuras are not just cast pistons. They are hypertecteutic (sp?) cast pistons, almost as strong as forged but lighter in weight.

 

[scotj77]

great info as always royalt

 

[Budget_Blaster]

I believe you are correct. Namura is actually a fairly new manufacturer (10 years?) but I think they are OEM on some bikes.

FWIW, I just tore my motor down and the Namura piston looks great. The cool coating is gone, but that is just for break-in anyway. This is with one season of racing on it. Contrast that to my last Wiseco (one season) that came out of the motor with cracks in the piston skirt.

And bear in mind, Namuras are not just cast pistons. They are hypertecteutic (sp?) cast pistons, almost as strong as forged but lighter in weight.

That's correct I didn't mean that they've been used since jesus was a boy but they're being used in oem stuff out of the box.

In terms of longevity a hyper will last longer than a cast or forged providing youre tuned correct.

A hyper piston has a higher amount of silicone and has a tendency to literally swell in the bore providing a good seal and uniformed wear.

 

[Budget_Blaster]

Just don't use hypersensitivity or cast in forced induction setups or on the bottle.

But who is really spraying or boosting their blaster?

 

[200+cc]

dont have many hours on mine yet (just it broke in) at this point just happy it runs good. the piston i got has a step on the exhaust side. it ends up being a little more responsive i guess like lifting exh port. i did a conservitive porting & polishing, didnt really open anything up but a lot of smoothing out. didnt lift exh port.. figured with styling of piston, it may be too much without having more aggressive mods. but with a couple other bolt-ons i've done its noticably stronger than stock. cant really say how much the step on the piston does for throttle response. but anyone who knows or builds engines knows, making power comes down to moving more air/fuel smooth & efficiantly. ive worked on motors as small as a 1.2cc for my r/c nitro truck and as big as a detroit diesel for a 42,000lb track trencher. big or small, whatever parts are in them (oem or aftermarket) they all suck when they are broken.. lol

 

[scotj77]

good work man. way to squeeze some power out of the blasty on your own. have some greens

 

[200+cc]

Namura piston seems ok so far.. Havent put any serious hours on it yet, but have given it hell. Also ended up widening 5 inches and cut swingarm and added 3 inches. Made rear grab bar/ gas can holder.. and aquired another blaster that I will keep pretty much stock. chomping at the bit here in Maine, trails dont open till June.