Your /5 and later BMW Airhead motorcycle has a well-deserved reputation for reliability and exceptionally long life. Regular oil and filter changes based on both time and mileage are necessary. Use of a quality oil and quality oil filter is highly recommended. There have been quite a few different filter numbers, filter styles, and methods of fitting them and associated parts such as O-rings, gaskets, shims, and oil cooler attachments, over the years of Airhead production. This article will attempt to cover all versions, models, situations. HOWEVER, the Author’s website has several articles, number 49 through 51D, THAT SHOULD BE READ; these cover things in more depth; things you REALLY NEED to know. Please be sure to read all those articles.
Failure to follow recommended procedures, particularly on /7 and later models, or any model with an oil cooler, can result in $$$ repairs. There is a critical white round large rubber O-ring used on the outer cover on models with oil coolers, and also used on later models without coolers. That O-ring must be in good condition, and under proper mechanical mounting pressure, in the proper way. A failure here can result in an engine rebuild costing at least $2000; and if the crankshaft failed, perhaps over $3500. Reading articles 49-51D on the author’s website AND the entire article you are reading will make you an INFORMED owner, highly unlikely to make an expensive mistake…or allow someone else to make such a mistake.