WR400 high compression pistons?

It is getting to be time to freshen the top end on my 2000 wr400 and I am thinking of maybe getting a slightly higher compression piston. Has anyone got a high compression top end in their WR? what is the hot setup? It is a stock WR , other than all of the free mods

I'll be doing mine this summer, but no changes for me. Compression is high enough as it is. Reliability can only deteriorate with additional mods.

Yamaha Engineers spend countless hours in R&D. These engines have such a good mix of performance and reliability, I will trust them and keep mine stock.

I just looked in the manual, the stock compression ratio is 12.5 : 1 on my 98 wr400.

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