Oil and Filter Changes, Procedures, Technical Information and the $2000 O-Ring. For BMW Airhead Motorcycles.
Including coverage of filters, shims, O-rings, canisters, etc.
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.
This article was completely revised by the author on 01-04-2007; updated 12-10-2007, 05/18/2013, 05/15/2014, 05/17/2014, and minor changes on 06/02/2014. Minor updating/clarification on 08/18/2015, 01/16/2016, 05/20/2017, and 06/20/2018.
Whether just changing the engine oil, and NOT the filter, or with the filter, take a 10 mile minimum ride to warm the oil; which is much better than a few minutes of 'garage warmup'. Remove the engine pan drain plug to drain the oil. Replace the oil drain plug using a new crush washer, torque to specifications, top up the oil to the proper mark (NOT screwing in the dipstick when taking a reading). On early Airheads you may 'burn' less oil, as many 'burned off' the first 1/2 quart or so, if you initially install the oil to less than the full mark. If you are also changing the oil filter, things are more complicated, very particularly so if you have a late model or any model with an oil cooler. I suggest you leave the drain plug out until the old filter is removed and the new one installed. I will get into the complications and technical details in this article.
This is the abbreviated information:
Once the old oil filter is removed and the new filter and other parts installed, you then have an oil chamber (canister) area that is relatively empty, just a fresh dry oil filter. All the oil from your engine's oil pump must pass through that oil chamber before it gets to the vital parts of your engine. You want to fill that canister chamber with oil, pressurizing the system, while putting only a light load on the engine.
The standard method is to use the starter motor to crank the engine, without allowing the engine to start. Some folks will remove the spark plugs, and make a tool for each spark plug cap, and thereby short the inside connection of the spark plug cap to the cylinder fins. That protects the ignition system. Others might just lay the spark plugs (with caps attached) onto the cylinders, with a sash rod spring wrapped around cylinder and spark plug, to keep the spark plugs positively in contact with the cylinder metal. Grounding the ignition by either method will protect the ignition parts, as would removing power to the ignition coil(s) primary winding(s). However, I do not advocate removing the spark plugs unless you need to for some other purpose. Another method: since the fuel tank is normally already installed; simply turn off the gasoline petcock(s), empty the carburetor bowls, and replace the bowls. Then I crank the engine. The battery and starter motor are more than capable of the needed one or two each ~6 second crankings. You can then ride to recharge the battery, or connect a trickle charger or Smart Charger.
On the center-stand, drain the warm/hot oil from the oil pan (yes, warm/hot...it is always best to take a ride first, that heats the oil, which drains much more thoroughly than cold oil or a garage engine run warmup). Be careful. The oil can burn you if too hot, so you may want to wait half an hour.
If you have a magnetic drain plug, which you should have, if not, get one, inspect it for particulate matter. Some fine oily powder, not feelable sharp particles, is OK and relatively normal. The F650 magnetic plug 11-41-2-343-498 fits, and so do aftermarket ones from your BMW dealer. Don't overtighten, use a fresh gasket.
Some folks like to do a particularly thorough oil change, and drain the cooler. BMW no longer says the cooler has to be drained. I agree. If you are changing the filter, then the oil cooler, if you have one, will drain anyway. If you are draining a cooler, or need to unfasten the hoses/pipes at the oil canister cover area in order to remove and replace the filter, then UNscrew the two 17 mm banjo bolts, letting the hoses hang down and let the cooler drain. It is BEST to use a socket wrench on delicate banjo bolts to avoid distorting them, and when reinstalling these banjo bolts you SHOULD BE USING A TORQUE WRENCH! FOUR fresh aluminum solid washers are needed. Have them at hand and available.