Hi Neal, that's why the 5.48mm insert is more like 8mm or so. I was scratching my head trying to figure this out, and thanks for the tip.
Fwiw, I took the insert out and re-tuned yesterday. Had to richen the high end substantially, and power became difficult to manage. The engine was more of an off/on switch, with "on" being a ridiculous amount of power and very hard to handle on a loose surface. Your drilled insert is going back in as we speak, and I'll re-tune when I get back out, then I will leave well enough alone.
BTW, love the engine Neal, you will be my source for the foreseen future. Thanks
