Last week I mangaged to thread my head button.

Today I fitted a new one and noticed my Cly head and the top off the piston was very pitted!!!![X(][][]

I have read in the thread below that is it due to too hight a Nitro content, I have been using 25%.
I will now switch back to 20% as my last bottle was, but will it be okay to run it with the pitting or will I need a new piston????

The compression seams to still be there.

http://www.rcuniverse.com/forum/m_23...tm.htm#2365609