Best piston for 290 big bore ?

Just picked up a 290 cylinder for my 06 YZ250F. Any suggestions on the best piston to use ? Will have stock cams, would like to run pump gas and will have a mild clean up on the head. Vet race and practice only.


I run a Wiseco single ring 4982M08300 piston, but I would probably suggest a 2 ring JE piston. The single ring doesn't seem to hold up too well without rocking in the bore for mx use.

I'm going to try the JE 2 ring piston next.

I just put in my 2nd 4982M, and the one I took out looked immaculate when I took it out after 50 hours. Proof to me it was a good design, great skirt shape, and overall happy in the engine. The JE part is probably fine, but check to make sure they still offer it. I don't remember seeing it in their 2011 catalog.

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