Did this restoration of a 38 yr old cutoff saw, go some parts off eBay and even was able to get some parts from Stihl. I used the 49mm "super" shortblock. It was ugly and had points, but I converted it to electronic with a trigger unit. I is great, but it will top out at 13,500 rpm. My Stihl regional tech guy said the old carbs had a valve in the carb to limit the rpms. I have the origional carb, but don't see anything like that on it. He said it was called a shaker valve that operated on the harmonics of the engine. I'm scratching my head. I know that is way to much rpm for the spindle and could be catastrophic, should the blade come apart at that speed. Does anyone know of a rev limiting trigger unit?View attachment 167798View attachment 167799View attachment 167800View attachment 167801