Good Piston for a 125cc Two Stroke?

[OhhShockzzz]

What is a good piston for a CR125 2 stroke?

[cr250harry]

Woosner or weisco forged pistons have always work a treat for me

[zotis777]

Bad things are sure to come

[frdbtr]

OEM, ProX, Wossner, or Wiseco.  All good pistons.

[x_JT_x]

Namura! If installed correctly.

[unboundnrg]

I use oem only. It's cheap and reliable.

[Beau 88]

Depends on how you ride really , trails and running through fields Namura or Honda OEM , Serious racing Wiseco or any other brand of forged piston. In either case warm your bike up good before you take off on it. Cast pistons are more forgiving to those that won't . I run Namura in my cr250 not a problem. OEM in my sons cr125 . 

[nino]

No Wiseco for me. The only failure i ever had in 30 years was with a Wiseco.

 

OEM pistons shrink too much...once really warm they just shrink too much which makes for that rattling sound and loss of power.

 

For me it's Vertex /Wössner

[OhhShockzzz]

Should I just do a top end or a full rebuild? 60% free riding and 40% on the track

[unboundnrg]

No Wiseco for me. The only failure i ever had in 30 years was with a Wiseco.

 

OEM pistons shrink too much...once really warm they just shrink too much which makes for that rattling sound and loss of power.

 

For me it's Vertex /Wössner

What causes them to shrink? Thermal expansion just makes them expand as they get hotter, right? Or do you mean that the cylinder expands more and leaves too much clearance? 

Edited June 11, 2014 by unboundnrg

[Beau 88]

What causes them to shrink? Thermal expansion just makes them expand as they get hotter, right? Or do you mean that the cylinder expands more and leaves too much clearance? 

?  called a worn out top end ?

[unboundnrg]

Well, not this time  ?

[OhhShockzzz]

Do I just do a top end or a full rebuild? 40% track and 60% free ride

[Beau 88]

Do I just do a top end or a full rebuild? 40% track and 60% free ride

Depending on if you have play in the lower rod bearing , and or noise . Horizontal play or side to side is normal Vertical rod play means you have a worn bearing so the crankshaft would need rebuilt or replaced . 

[kauko40]

Vertex, oem or Prox

[AdrianTenerife]

Namura pistons are about 50 dollars, heard of pretty bad reviews though and some possitive. Do you have experience with that brand?

[x_JT_x]

Namura pistons are about 50 dollars, heard of pretty bad reviews though and some possitive. Do you have experience with that brand?

Lots of experience, 0 issues. Granted they have all been 2 strokes.

[pc_151]

Stock piston is made for the bike. Don't get wiseco crap. Stock last longer.