Piston adwise 2 stroke

mosslander
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mosslander
Edited Date/Time 1/27/2012 2:38pm
Wish piston is best for twostroke, cast or forged and why it's best.
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mx400bee
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mx400bee 7/17/2010 4:14pm
7/17/2010 4:14pm
A cast piston is lighter and dimensionally more stable and can operate at closer tolerances making more power however, it is somewhat more brittle than a forged piston. I`ve always used cast in 250 and smaller engines and never had any problems.
In big bores I mostly run forged pistons because the added weight of the piston and larger tolerance needed for expansion seem to tame the power more to match my skill level or lack of shall I say. Also, if an engine has been modified to the point to where detonation is a possibility a forged piston would live longer due to higher strength.
mosslander
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mosslander 7/18/2010 3:04am
7/18/2010 3:04am
mx400bee wrote:
A cast piston is lighter and dimensionally more stable and can operate at closer tolerances making more power however, it is somewhat more brittle than a...
A cast piston is lighter and dimensionally more stable and can operate at closer tolerances making more power however, it is somewhat more brittle than a forged piston. I`ve always used cast in 250 and smaller engines and never had any problems.
In big bores I mostly run forged pistons because the added weight of the piston and larger tolerance needed for expansion seem to tame the power more to match my skill level or lack of shall I say. Also, if an engine has been modified to the point to where detonation is a possibility a forged piston would live longer due to higher strength.
Thank's mx400bee for the info about it.
CamP
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CamP 7/18/2010 9:11am
7/18/2010 9:11am
I always use OEM cast pistons.
typhoon67
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typhoon67 7/18/2010 9:13am
7/18/2010 9:13am
Detonation is going to damage any piston, forged is a more dense material and will wear longer, it has not got better strength regarding detonation.....this issue must be corrected (jetting, timing, fuel quality) or a failure will result no matter what type piston is used....never use either more than 50 hours.
2 strokes do not like pump gas.....

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mx400bee
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mx400bee 7/18/2010 5:18pm
7/18/2010 5:18pm
typhoon67 wrote:
Detonation is going to damage any piston, forged is a more dense material and will wear longer, it has not got better strength regarding detonation.....this issue...
Detonation is going to damage any piston, forged is a more dense material and will wear longer, it has not got better strength regarding detonation.....this issue must be corrected (jetting, timing, fuel quality) or a failure will result no matter what type piston is used....never use either more than 50 hours.
2 strokes do not like pump gas.....
What you are saying is absolutely correct however, cast pistons have a much higher silicone content than forged and thats what makes them more brittle. A forged piston is more dense, (malleable) has much less silicone, and would last longer if detonation were to occur. So, if it wears longer and won`t crack as quick wouldn`t that make it stronger?
typhoon67
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typhoon67 7/18/2010 10:01pm
7/18/2010 10:01pm
This was my statement: "it has not got better strength regarding detonation"
so yes there is greater durability, greater "cracking" resistance, and more strength....but this strength does not give it any more detonation damage resistance.
mx400bee
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mx400bee 7/19/2010 5:06am
7/19/2010 5:06am
When detonation occurs a piston with a lower maximum strength yield (cast) is going to break quicker than one with a higher maximum strength yield (forged). Plain and simple
typhoon67
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typhoon67 7/19/2010 7:17am
7/19/2010 7:17am
When detonation occurs in a hi performance 2 stroke engine pistons do not "break" or "crack", they melt.........and will blow holes in the dome, cast and forged melt at almost the same temperature so a forged will not resist detonation damage any better than cast.........tensile strength is not the issue......engineering 101.
Silicone is added to cast pistons to control growth and reduce the "brittle" properties.
moto314
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moto314 7/19/2010 10:19am
7/19/2010 10:19am
Higher silicon content in pistons results in a much lower fatigue strenght at elevated temps.
mx295
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mx295 7/19/2010 8:48pm
7/19/2010 8:48pm
OEM
Halfast816 7/20/2010 5:33am
7/20/2010 5:33am
The temp at which aluminum melts is lower than the temp of combustion. The layer of atomized fuel protects the piston at moment of combustion. Detination is the preignition of the layer burning it off to soon causing the damage to the top of the piston and sometimes head. I bet most whom have answered know this , but I like typing anyway. Stick with OEM if still available depending on age of bike.
moto314
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moto314 7/20/2010 2:54pm
7/20/2010 2:54pm
Wiseco hands down.
mosslander
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mosslander 7/20/2010 3:00pm
7/20/2010 3:00pm
Thank's everyone for the information and now I wonder wish one I would chose Mitaka,Vertex,Namura or Prox ?
typhoon67
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typhoon67 7/20/2010 3:46pm
7/20/2010 3:46pm
Tarabusi........
mosslander
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mosslander 7/21/2010 4:40am
7/21/2010 4:40am
typhoon67 wrote:
Tarabusi........
Thank's typhoon67 . Do they make to my 87 cr 250 and where do I buy them?

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