OEM or aftermarket 2stroke piston?

I know everyone is telling you to 144cc that bike. I highly recommend sending it to: http://www.chadwattsperfections.com/

He is building beasts.

Pro X is the same as OEM.

Both manufactured by ART in Japan

I always use Wiseco Pro-lite pistons. Never had an issue, and they're forged, not cast. They're better then OEM. I've changed my last two pistons at 60hrs. I could have got away with just a new ring. The pistons still looked new, and the cylinder is perfect. Harder on your cylinder?? That's a new one!!!!

This question will get lots of opinions. I have on my work bench 5 used pistons that all have a full race season of enduros and hare scrambles (60 + race hours) 2 of them are wiseco and 3 are vertex. the 3 vertex look like I could throw new rings on them and put them right back in service. The 2 wiseco pistons look like they have been through a war..
I am sticking with vertex..

forged pistons expand more during the heating cycle thus have to have more clearance with the cylinder bore. Cast pistons can be run with tighter tolerance. This could lead to more wear from a forged piston rocking more in the bore till it gets up to operating temp. The skirts on the wiseco pistons I mentioned in my above post is where they looked beat up the worse.
I can tell you that cast vertex pistons make less noise "knocking" when you first start up your cold engine. First time I ran a wiseco I though something was wrong when I started it right after a rebuild from the knocking coming from the cylinder.
Vertex also come in ABCD sized to match your cyl. wiseco just makes one size fits all. so if you have a C or D cyl its gonna knock even more till it warms up.. Just my observations, based on my experience. This is a topic that will get lots of opinions, like what premix do you recommend?

A forged piston takes the shape of the bore during the first heat cycles there for sealing better than a cast piston. They require you to do complete heat cycle break ins and a lot of people don't so they'd have a bad rep. Get a wiseco gp series

I always ran Wiseco in my two strokes. They are noisy until the engine is at operating temp, but I never had a skirt crack or premature cylinder wear. Big horsepower engines always run a forged piston.....

Plus they are made right here in the USA

I won't run anything but cast pistons. I'd rather have the rings wear out than have the piston stick and take the cylinder with it. The forged pistons don't do well with being run at the edge of fuel/air mixture and if combustion temps get higher than expected. In my experience, forged pistons always make a mess of the cylinder when they overheat.

There is so much variability between the relative air density, fuel quality, and tuning using static jetting and static ignition maps to think you are safe from sticking the piston each time you run a two stroke. But this only applies if you are making power and not just spooging your bike around the track.

http://www.ebay.com/itm/NEW-GENUINE-HONDA-OEM-PISTON-KIT-2005-2007-CR12…
or

http://www.ebay.com/itm/GENUINE-OEM-HONDA-TOP-END-KIT-CR125R-2005-2007-…
There are probably others.

You're welcome.

Also, avoid Namura pistons like the plague. You're doubly welcome on that one.

I like vertex

I've been running Wiseco Pro Lite pistons in my '07 CR125 and have had no issues.