I just got my cylinder back from Eric for my sons cr 85. He bored out the cyclinder to 52 mm. My question is do I need to run race fuel or a mixture of race fuel in the new cylinder. We have been running pump gas 92 octane in his previous motor. We did try some airplane fuel mixed 50/50 with 92 octane pump gas. The bike to me ran a little better with the mixture of airplane fuel but my son didn't seem to notice a big difference. Want to make sure I don't hurt the new cyclinder.