RE: SuperTiger .45 HELP
Well Ed, I'm not sure that ST puts that instruction with every engine. I've been running ST engines since 1968 and have owned at least 20 of them. Looking through four different engine boxes, and I found it referenced once.
They also state that they preset the idle screw, so no initial adjustment is required. Now on the ST engines that I have run, some are ring, others lapped, while others are ABC. All engine require breaking in, not only for the piston/sleeve fit, but also to allow the rod to lap in it's fit with the wrist pin and crank pin. While an engine is still tight and coming in to a fit it requires slightly more fuel at idle than a well broke in motor. Generally an engine will idle better in the air than it does on the ground, because it has the airflow to help maintain the engine running while idled back. What it may not do well is throttle transition, but I don't worry about that until the engine has some time on it. Once the engine fit has stabilized it is worth my time to adjust the bottom end, but till then I don't try to hit a moving target.