I have a question about oil filters. I just did the first oil change on a new to me 1992 R100GS with oil cooler. The filter I removed was a HiFlo HF161. I am sure this is not the correct filter for the bike, the filter sets inside the engine case about 18mm. From what I am told by the previous owner this filter has been in the bike for about 2000 miles. I replaced with the proper BMW filter. What damage has been done to the engine?