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Author Topic: namura piston kit?  (Read 3618 times)

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Offline 1989kawasaki

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namura piston kit?
« on: March 06, 2011, 01:08:36 PM »
« Last Edit: March 06, 2011, 01:10:16 PM by 1989kawasaki »
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1977 RD400
1989 CR250
1988 CR500
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Offline sandblaster

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Re: namura piston kit?
« Reply #1 on: March 06, 2011, 02:14:40 PM »
Their ads sound great.
However, I'm not certain I would want a cast piston in my K5.
From what I have seen there are less failures with forged.
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The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline 1989kawasaki

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Re: namura piston kit?
« Reply #2 on: March 06, 2011, 02:18:37 PM »
oh, then i do not want a cast piston in my bike
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bikes

1977 RD400
1989 CR250
1988 CR500
1978 Z50
2009 Harley super glide custom

Offline sandblaster

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Re: namura piston kit?
« Reply #3 on: March 06, 2011, 02:20:15 PM »
Everybody has a different opinion.
Wait and see what other engine guys say before you make up your mind.
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The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline 1989kawasaki

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Re: namura piston kit?
« Reply #4 on: March 06, 2011, 02:21:17 PM »
after seeing what has happened to other people, i dont really want a cast piston
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bikes

1977 RD400
1989 CR250
1988 CR500
1978 Z50
2009 Harley super glide custom

Offline alward25

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Re: namura piston kit?
« Reply #5 on: March 06, 2011, 04:48:23 PM »
They are a hypeutectic piston.  It is cast but with a higher silicon content.  They can clearance like the the stock cast piston but are about as tough as a forged.  I have run the Namura in other apps with no problems.  You don't get the cold piston cylinder slap like the forged pistons do until they warm up.  I have run hypeutectic pistons in sb fords and chevys and they held up awesome with 400-500 horse.  I have not run one on my K5 because I have not found them with a window.  I might have to try one and report back.  I have read of people having problems, but I have heard the same of wiesco too.  You sometimes only here about it when something goes wrong and not right.  If it is right you are out riding and not at home with a broken bike typing on a forum about how it failed.  If you try one let all of us know!!!!
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Offline DFL BIG BORE

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Re: namura piston kit?
« Reply #6 on: March 07, 2011, 07:10:48 PM »
forged pistons are for steel bores,cast pistons are better suited for nicosil plated bores.you think you are smarter then the engineers who designed your kx?cast piston failures are the result of poor jetting choices,piss pore matinance ,and crazy premix ratios like going with a 50:1.just my 2 cents
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Offline Marco810

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Re: namura piston kit?
« Reply #7 on: March 07, 2011, 08:10:50 PM »
Here's what kind of beating a forged piston can take, ended up that way due to cylinder problems, but still ran fine when i pulled it!

Ive never run a cast before but i heard when they go they tend to grenade



 
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Motorrad

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Re: namura piston kit?
« Reply #8 on: March 07, 2011, 08:12:45 PM »
Quote from: Marco810 on March 07, 2011, 08:10:50 PM
Here's what kind of beating a forged piston can take, ended up that way due to cylinder problems, but still ran fine when i pulled it!

Ive never run a cast before but i heard when they go they tend to grenade



 

 :-o :-o :-o :-o  Is that a wear spot or a Puddle that has formed//!!    sideways shot please..
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Offline Marco810

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Re: namura piston kit?
« Reply #9 on: March 07, 2011, 08:19:36 PM »
Ill see if i can find it tomorrow

and yeah it differently bulged (for lack of better words)
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