I have looked through the manual a couple of times trying to find the red line rpm and rev limiter rpm and have not had any luck. Does anyone factually know these numbers? I may be chasing a ghost and causing myself to lose sleep over this high speed miss. This evening I hooked up my tiny tach and ran the engine up sitting in the garage several times. It begins the steady missing at around 6300-6500 rpm range. Tried it with and without the air box lid and get somewhere in the neighborhood of the same readings. Maybe this is the rev limiter I am feeling. Some have claimed to hit the limiter at 65 mpg but mine won't run that fast. I thought it was the plug or plug wire but I seem to have fixed the missing at lower rpm by repairing the plug wire. Thought it might be the plug but get the same results with a new plug. It still seems to be running rich at lower rpms and leaning out on top. I am going to raise the needle from 4th with no washers to 4th and 2 washers tomorrow and see if the bottom end will clear up some. It may be that the 158 is still lean on top. I have a 160 or 165 I guess I can try. That should answer the question if it is to lean on top and then work backwards. Makes a fellow want to start drinking sasparilla, huh?