I have a lot of respect for the knowledge and skills of Brian Miller but I disagree with his notion on this issue. The purpose of a detergent is to dissolve contaminants and keep them in suspension. Normally, this was done so that a full-flow oil filter could remove those contaminants down to a specified size (micron) and keep the oil fairly clean. Kohler K's do not have oil filters so in order to keep the oil clean, the owner must change it every 25 hours of operation maximum.
If owner's do not adhere to that schedule, then the contaminant level in the oil will continue to build and then it becomes an abrasive mixture that begins to cause accelerated wear. This becomes a domino effect. The more wear that takes place, the more the oil becomes contaminated and that accelerates the wear.
Perhaps Brian's point is this. If you use non-detergent oil, all those contaminants will just settle on engine parts or in the bottom of the oil pan and they won't be circulated in the oil. Sounds like a good plan, right? The downside to this theory is this. Those contaminants will not get flushed out during an oil change so they will stay behind as an ever-thickening coating on the inside of the engine. Yes, these are called air-cooled engines but you cannot dismiss the fact that the oil itself must be cooled as well. The only way that the oil will get cooled is if it can come in close contact with the engine block and pan.
Those are my thoughts.