I have been running 36:1 klotz original techniplate since day 1 on my new 661 arctic. I have 7 tanks on it so far. The saw has the old style boot and it's been bogging. So I decided to change the boot....which pretty much requires pulling the jug. It's a total pain to drop the tank with all the wiring on the arctic. seems to burn pretty clean inside the muffler can. Big mark on the piston. Oil fault? Klotz does say 13k limit for orig. techniplate. But I would only go over that piss reving so? Or maybe Hd2 let something get through? This is my 11th or 12th 661 and this is the first time I've seen this and it's the first time I've used original techniplate. coincidence? see video for top of piston - it's wet and black. No transfer wash showing. Video is posted after pictures. inside the jug. Not exactly clean, like I've seen with the likes of mobil 1, honda hp2, and schaeffers. vid - shows much more than the pics. Maybe it would run cleaner at 40:1?