Thats the low reach spark plug yes? Dont you have issues then with exposed threads of the head?You say 9 but there are two types of 9s boss. I run a non-projected tip because of this exact scenario and my aggressive timing curves. Projected tips will
Act is flame throwers and duplicate this scenario more times than not. CR9E is my current plug in a stock bore setup and many degrees advanced timing. I do watch the plug often and replace it frequently in heavy weather swings here in TX and time my bike accordingly. Colder drier air gets a few degrees retard to keep the piston happy.