All motors are different, we had 2 motors and one ran best at 1080 and the other at 1150. As for how hot is too hot? Well aluminum melts just over 1300…
Yeah that is my concern. On my TM K9b my one cylinder seems to like to run really hot. I have gone up to 1250º even seen 1275º F. And it seems like I could lean it down even more because spark plug still seems pretty wet. But I am concerned with going any leaner with the exhaust temps getting that high. Didn’t know if anyone else ever got their exhaust temps that high.