Pre-1970, the BMW engine had oil slingers instead of oil filters. In a different era most owners of these older BMWs would have the tools and the time to clean or replace their slingers at the factory recommended 45,000 miles. These motorcycles are no longer typically in daily use so if you have one and don’t know whether it has had its slingers cleaned, they could be due even at 20,000 miles due to disuse, age and neglect. The process involves removing the engine, disassembly, cleaning and assessing for any other needed repairs while in there, and finally re-installing the engine. Below are two R69Ss that we have here in different stages. (1) is almost finished and (2) has just begun. The next set of pictures illustrates the slinger cleaning from R69S (2). To read more on this see Bench Mark Works’ article: http://www.benchmarkworks.com/articles/tech/oil.html