After market pistons for a Two stroke.

[Panzerman]

Iam rebuilding my daughters Polaris 250 trailblazer two stroke and looking at the various pistons for it. Ive used Namura before in my sons and it seems to be holding up well. I was going to try a WSM piston in the this one. I prefer a cast piston to a Wiseco forged piston because 11 year olds dont let things warm up properly no matter how much you harp at them and forged pistons can cold sieze. Anyone have any experience with WSM? I have also heard the factory Polaris pistons dont hold up well, alot of them crack skirts on the net, although this piston skirts look well, the head is damaged so Iam replacing it.

 

[DieselTech]

WSM or Pro-X will do a great job for you. make sure you change the wristpin bearing also. Get the Cylinder bored and crossshatched.

Lastly remove the injection system. The oil injection is poor, go to premix at 40:1 with a good 2 stroke. I run wiseco in my 250R and banshee

 

[XJ1100]

Any cast piston will do just fine - as long as it is setup properly. I have had great luck with SPIs in snowmobiles, and they are fairly cheap.

 

[Panzerman]

I was going to just put a new piston, but I did feel some burrs(no scars or groves though) in the cylinder so I bought the next size oversize and Iam going to have it bored to fit the new piston. I wasnt going to get a new wristpin bearing, but I might since Iam going the full route now. Polaris has alot different oil injection system than the Japanese bikes, it supplies alot more oil and is safer, but not super fool proof. I still mix the oil about 60:1. I might eliminate it and go with Yamalube 2R. Its the girls quad and you know how kids are and I will have to beat in their head about the importance of (PREMIX ONLY). Thanks for the responses.