F650 Oil FAQ
Edited by Winter #1935, Feb 2007
Special thanks to a trusted "consultant" who wishes to remain anonymous
Please read the Disclaimer before
attempting any work in this FAQ.
Last Updated: 2 June 2007, by Winter #1935
- General Oil Information
- Oil and your F650
- Oil Circuit Maintenance
- Misc Oil Questions
- Can I get more power from a different oil?
- Do some oils result in the clutch slipping?
- Can I add an oil cooler to my F650?
- What if I do not drive more than 6000miles/10000kms in a year?
- Can I mix different oil types?
- What is this white gunk under my oil cap?
- Should my oil look like a mocca coffee?
- My bike is overheating. Could oil be the problem?
- What do I do with my "used" oil?
- Can I use SK... SL... oils in my bike?
- How do I get an oil assay done?
- What is it again that is aluminum and wears inside the engine?
- Do additives (Zinc, Phos and Moly) make motorcycle oils more expensive?
- Should I worry about fresh oil turning dark quickly?
- What temperature should my oil be?
For other related FAQs:
Oil. The blood of the modern combustion engine, plays an important role in the reduction of friction. Although oil may aid in the reduction of friction within an engine, outside of the engine it generates many heated debates. Should I use Synthetic or Mineral oil? What is the best viscosity I should be using? How often should I change my oil? Previously this FAQ contained many opinions on various topics, leaving plenty of confusion. This has been changed to provide you with factual information where possible. Experimental data is also now available, so you can see why some questions have been answered in certain ways. Where there is still debate, the arguments have been summerised into something more concise.
Please make sure you read this FAQ carefully. Please do not post messages in the forums asking "what oil should I use?". Use the information provided in this FAQ to make up your own mind over the most appropriate oil. If you have a question not answered by this FAQ, by all means ask in the forums, and you should soon have an answer.
|BMW Oil Related Servce Bulletins|
BMW has released several service bulletins related to oil and the F650 motorcycles. You can find more details in the Service Bulletins FAQ.
Service bulletin 2855 from 1998 covers the use of SJ engine oil in BMW motorcycles (SJ specification oil is not approved for use in BMW motorcycles).
Service bulletin 11 002 05 (015) from Feb 2005 covers the overfilling of oil in GS/Dakar/CS model bikes.
|Oil Specifications Change with time|
|It is important to note oil specifications change over time. This can be due to many reasons, such as more modern engines requiring differing levels of additives. The main content of this FAQ was written in March 2007, so if several years have past, it may need substantial revision. However for the most part, the FAQ should remain fairly accurate.
|It Really Is Simple!|
|Oil choice is really simple, so stop asking us "Is it okay if I use oil X, Y or Z?":
If you experience problems after changing your oil, then check your choice of oil again, or change it to something else. If you are still having problems, check all the work you have done on the bike. Finally if you honestly think it is not the oil causing your problem, ask about it in the forums. The Hard Starting / Poor Running FAQ should help you. If you have any doubts about an oil, have an assay done.
- Work out what ambient temperature you will be riding in (min. and max.)
- Using the chart below, work out a good viscosity rating.
- Work out if you want to use Synthetic / Semi-Synth oils based on the arguments provided in this FAQ.
- Go shopping. Remember SJ oils are not recommended by BMW, and do not use EC (Energy Conserving) oils.
- If the viscosity rating you want is not available, try something else close to your preference. You did read the section on what these ratings mean right?
General Oil Information
Motor oils are required to do many things at the same time, which is why formulating oils is such a difficult task. Engine oil is expected to provide a protective film, to prevent metal to metal contact (wear) and reduce friction. It must help remove heat from engine surfaces (i.e. piston), and flush away wear particles. It also aids in sealing the piston rings, serves as a hydraulic fluid (i.e. hydraulic lifters or chain tensioners) and in some motorcycles, transfers power through a wet clutch assembly and lubricates the gearbox. In general terms, all of the above properties can be obtained to some extent using a simple basestock (and did until the mid-30's). But in mankind's never ending quest for power, engine power density continued to increase, stressing the basestock's natural lubricating abilities. Since the 30's, lubricant additives have been utilized to fortify the basestock's natural properties: by minimizing wear and deposits, reducing friction and harmful deposits, stabilizing the viscosity, and minimizing rust and corrosion.
Viscosity is defined as the resistance to flow, and varies by temperature, pressure, and shear. To simplify, think of that bottle of pancake syrup in the refrigerator. It flows very slowly (high viscosity). Heat it up in the microwave, so you can pour it on some pancakes, and it pours easily (low viscosity). Of course, you know how scientists have to have ways to measure these kinds of things, so they invented several different ways (to keep us confused).
Saybolt Universal Seconds (SUS) is an old method, which measures the time it took (in seconds) for a measured quantity of fluid to exit through a "standard" orifice at a given temperature. The modern method uses different apparatus (automated), but is based on the same principle, and reported in metric units of centistokes (cSt), also known as mm2/sec. SUS was typically measured at 100°F and 210°F, while cSt is usually measured at 40°C and 100°C.
The term viscosity index (VI) is based on the relationship between the viscosity of the fluid at these two temperatures, and can be derived using a large table in an ASTM test method. Suffice it to say, that 100 was set as an arbitrary number; as the VI increases, the viscosity of the fluid becomes more stable as the temperature changes. A regular motor oil may have a VI of 110 - 120, a premium synthetic of 150 - 160, and a shock/fork oil of 200+. The VI is important to motor oils, as they need to have a low enough viscosity in the cold to be pumpable (to lubricate at start up), while having a high enough viscosity at operating temperature to provide a thick enough oil film to prevent metal to metal contact.
Those scientists developed a set of specifications to define the viscosity of different grades of motor oil. While it is always under revision, it is referred to as the SAE J300 viscosity specifications. Due to copyrights, it will NOT be reproduced here, but can be found at the Infineum website. I would recommend printing a copy to refer to for the rest of this discussion.
You can also find the following useful PDF about viscosity ratings.
|Example SAE J300 Viscosity Specification|
SAE 10W - 40
|The first number (10) indicates the winter rating
|The second number (40) indicates the viscosity at 100°C (212°F).
Multi-weight engine oils come with two viscosity designations. The first part is the winter, or W rating, which corresponds to conditions encountered in cold weather starting. There are two different viscosity specifications these xW oils must meet.
- The low temperature cranking test is to simulate the viscous drag felt by an engine attempting to "turn over" at the designated temperature. The test apparatus is a rotor-stator type, and utilizes a "quick cooling" cycle, before measuring the torque (drag) the oil creates between the small gap between the rotor and stator (again, those clever scientists have figured out a way to measure that drag, called cP, or centipoise). The lower the drag, the easier the cold weather starting, and the lower the "W" number (for comparison purposes, the viscosity roughly doubles with each 5°C drop in temperature). Note that each W grade is measure at a different temperature.
- The second test is called the low temperature pumping viscosity, and is designed to measure how fast the cold oil will flow toward an oil pickup in an oil pan. The reason that this is important, is that if it doesn't flow fast enough, the oil pump will suck air instead of oil (air is generally a poor lubricant). This test is sometimes called "air binding", and is to address a property found in some petroleum based oils. Normal petroleum oils (non-synthetics) contain some wax, which can crystallize into a latticework that resembles a sponge. This latticework traps the oil in the cells, and prevents flow. An additive, called a pour point depressant (PPD), can be used to disrupt formation of the latticework (wax forms needles that settle instead). Synthetics generally do not have wax to form this latticework. Again, notice that the temperature decreases with lower "W" numbers. There is also a minimum kinematic viscosity specification, but multi-grade oils should never have a problem meeting this - it typically applies to a single grade oil, 20W, for instance. So now you know what that first number (xW) in the oil's viscosity means. You probably don't think it means a lot to most motorcyclists (unless you're a cold weather die-hard), but it'll show up again later on.
The second number designates the viscosity of the oil at 100°C (212°F). This is in the ballpark for operating temperature, but most bikes can sometimes run hotter than this (250°F or more). The kinematic viscosity at 100°C defines the second number in the oil's viscosity designation, and is strictly a matter of seeing where it falls in the chart. Note that the oil also needs to meet a second viscosity specification (high-temperature high-shear - HTHS) which simulates the viscosity provided at 150°C under pressure (cams/lifters, for example).
That about covers viscosity, with the exception of noting a few things that can affect it. Fuel dilution of the oil can significantly reduce the oil's viscosity. The shear found in a bike's gearbox and clutch can shear polymers, reducing the viscosity. Normal oxidative processes tend to increase the oil's viscosity (i.e. sludge and varnish precursors). Extreme loading with dirt and soot can also increase viscosity. Unfortunately, by just measuring viscosity, you may not notice a change, as these things can combine and offset each other.
Oil and Polymer Chains
Multigrade oils are made with a basestock that will enable them to meet the W-rating...I.e. a 5W oil is made with a much lower viscosity base oil than a 10W/15W/20W or straight 40 (in that order). They then add viscosity improvers (polymers) as required to increase the warm temperature viscosity (and an additive package that includes antiwear and antioxidants). The wider the viscosity spread (or conversely, the lower the viscosity of the starting basestock), the more (not LONGER chains) of this polymer are added. A straight 40 probably has none. So the 5W50 has a LOT of polymer to get chewed up (And that 5W basestock alone doesn't make as thick of a protective oil film as a 10W or higher). The quality (viscosity index) of the starting basestock will influence how much VI improver is required (better basestock = less VII). The polymers used for VII also vary, some are more shear stable than others.
Some other things that can affect the viscosity...water/coolant content [from condensation or water pump seal leak] or fuel dilution [suggest taking samples of oil soon after taking a ride long enough to boil these off], Noack volatility of the oil [the part that gets volatilized is typically low viscosity, so the higher viscosity stuff gets left behind and artificially increases the viscosity - a cheaper and/or lower W-grade oil would be expected to show this more - making it look better - but less a concern with SL oils]. And of course, the target, shearing of the VII (operating temperature and typical operating RPM may affect this). Assuming you define lubricity as coefficient of friction, I'm guessing a 4-ball wear test would be the cheapest (although not cheap) way to go (see Amsoil's site).
- SH vs. SJ - Phosphorus (P) content was lowered from 0.12% to 0.10% (P is a poison to catalytic converters). Allowances were made to only do this to low viscosity oils (10W30 or lower), although most manufacturers did it across all viscosity ranges to make things simpler. The P is an integral part of the antiwear package, which means that the antiwear content is lower (I.e. used up faster than before, esp. by severe service/extended drain). The P also serves as an antioxidant, so more stable oils (synthetic) have more P available to act as antiwear, as it isn't splitting duty as an antioxidant as much. Solution is going to more frequent oil changes.
- SJ vs. SL - more stringent engine tests and viscosity control require better/more additives and higher quality base oil (both add to price, not to mention the skyrocketing raw material cost of a barrel of oil). P content is the same (although it was originally planned to drop to 0.08%). SL was approved July, 2001 if I remember correctly, SJ will be officially obsolete by 7/2002 (time to clear the pipeline of old product).
- SF/SG/SH/SJ are all old obsolete categories. SM is current (and theoretically supercedes all the previous categories. Please note that the "S" stands for SPARK ignition (i.e gasoline engines). Note that "C" stands for COMPRESSION ignition (i.e. diesels) - Like CF, CI, CJ. Some oils meet BOTH.
- Oil specification "SI" was skipped to prevent confusion with the International Scientific (metric) units system. SK - was skipped due to the Korean refining company Yukong changing their name to SK Corp. just prior to the category (again, to avoid confusion) Motorcycle Oil Specifications (MA, MB).
- Some motor oils now contain friction modifiers that can be detrimental to wet clutches. These can usually identified by "EC" or "Energy Conserving" stamped on the bottle (look for the "donut").
Oil and your F650
F650 Oil Circuit
The engine used in the F650 and G650X models is based on the Rotax 654 engine. It has a dry sump, so unlike many modern bikes, the main oil tank is not located at the base of the engine. Instead, a second oil pump is used to scavange oil from the bottom of the motor, and pump it back to a remote tank. The diagram to the right shows the main oil circuit. (A wet sump motor has the crankshaft dipping into the surface of the oil in the oil pan and flinging it around, in addition to the pumped oil. If the level gets too high, the crank acts like an eggbeater and whips the oil into froth or foam (that looks almost like meringue)... which has GREATLY diminished lubricity and viscosity).
Oil System Components
Please click on the image to the right to see the oil circuit:
- Delivery pump
- Oil tank
- Check valve
- Oil filter
- Control valve
- Low-pressure line (gearbox)
- Low-pressure line (clutch)
- High-pressure line (crankshaft)
- High-pressure line (big end bearing)
- High-pressure line (camshafts)
- Chain tensioner
- Spray nozzle (for piston)
- Oil sump
- Suction pump
Note the two oil pump drive gears are plastic. To get to these two pumps, you need to completely remove the clutch.
F650 Oil Consumption
- Nearly every engine uses oil, some more, some less. But there is a formula saying that that an oil consumption of 0,1 litre per 1000km per 100 ccm is normal.
- Oil consumption on non-GS. Before you blame it (all) on the engine, remember that oil itself is volatile. The hotter you run it, the more you are likely to use due to evaporation of the volatiles off cylinder walls, PCV venting, etc. Not all synthetics are created equal. If you want to comparison shop, look up the technical specs on the oil you are using/thinking about using, and look for the Noack Volatility (@250C). In simple terms, it's the percent of oil you can expect to evaporate off at that temperature. The higher the number, the more volatile the oil (and the more you'll use under hard/hot conditions). Good news is that once you've burned off the volatile portion, the harder it is to burn off what's left (next time you only burn off the volatile part of your top off, a much smaller loss). The bad news is that the volatility of the oil increases, since the remaining non-volatile parts are generally higher in viscosity as well. But since the clutch/gearbox chews up the viscosity improver molecules (thickener), they offset each other to some extent. In any case, volatility is only ONE of the things to consider when shopping around for oil.
- Many people report their F650 bikes use little or no oil between oil changes. An example comment from Flash #412: I've ridden six F650s as hard as possible, WFO for hours on end. Four were Funduros and two were GSs. None of them ever used a drop of oil as near as I can tell.
- Just done a trip away and for the first time, I have had to add oil. The first day managed about 1200km, the next day was 700km, then back home with 700km and the final day was 1200km. I rode a bit faster than I normally do, must admit that my trip was fun, BUT this time
I had to add about 700ml of oil. Normally, I cruise at about 100kmh, this time it was 110 most of the time, with some bursts to 120-130kmh for some distances.
My trip was over 4 days and the average day temperatures were in the mid 30's deg C jack
- I usually use about 100ml of oil every 2000-3000km or so. I have a small oil leak at the clutch cover, but this has been a fact since before that happened. It started two years ago after I had cleaned and upgraded some parts in the carbs (=leaner mixture). Before that it didn't consume any oil at all. spakur #1117
F650 Oil Change Frequency
There has long been debate over how frequently you should change your oil. The recommended frequency is every 6000miles/10000kms and at least once a year for the F650. However many people "feel" for one reason or another they should change the oil more frequently, usually 3000miles/5000kms. Thus the question is: How often should you change your oil?
Short Answer: The BMW recommended oil change interval of once every 6000miles / 10000kms is highly recommended as an oil change interval for your F650. Oil assays show a rapid change in the oil in the first 500miles after an oil change, and very slow change for the next 5500miles. In the assay analysis below, there is very little difference in the oil between 3000miles and 6000miles, so you are simply wasting money and oil.
|Do not forget you should change the oil as a part of the first service at 600miles/1000kms. This is probably the most important oil change as the sump plug and oil filter will contain plenty of metal from the engine after it was manufactured.
Long Answer: In order to dertermin the most effective point to change oil, is a science - not an art. Just because you "feel" changing your oil every 3000miles/5000kms is better, does not make it better. As oil ages, its qualities change / degrade. The ability of the oil to perform its function will change. these qualities can be measured by taking a sample of oil, and measuring specific qualities - however this can only be performed in comparison to the original oil used in the engine. An oil assay the common term user in this context.
Thus we perform an experiment, where the objective is to determin the best point at which to change your oil. There are two competing theories: the first being oil should be changed more frequently than BMW specifies, and the second being the BMW specified frequency is sufficient. For the purposes of this experiment, several Chain Gang members participated, using a variety of oils.
Method: Each individual performs an oil and oil filter change as per normal. Before refilling with clean oil, a sample is taken for "base level analysis". At regular intervals (approximately 1000miles), further samples are taken for analysis. The charts below show the results of the analysis of the assays performed. Each chart has the milage associated with the oil sample on the X-axis.
Figure 1: Oil Acid Neutralizing Capacity
Figure 2: Oil Viscosity Fuel Dilution vs Milage
Figure 3: Oil Ph and Zn Levels
Figure 4: Iron Wear Metal Concentration vs. Mileage
Figure 5: Aluminium Wear Metal Concentration vs. Mileage
Analysis: Within the first 500 miles, there is a significant change in the oil. However there is very little difference between oil at 3000miles (5000kms) and 6000miles (10000kms). Thus experimental data shows changing your oil at 3000miles or 6000miles makes very limited difference. You are simply wasting oil and money.
Note: Every oil is designed for different operating conditions. For example if you are using a SAE 10W-30 oil in +30C weather, the properties of the oil are likely to degrade faster. The BMW "Maintenance Instructions" for the 2004 GS suggests: Temperatures above or below the limits quoted for the individual SAE classifications are permitted for brief periods only. In other words if you are operating outside the recommended temperatures for long / regular periods, you may want to change your oil more frequently.
Some other common arguments about oil change frequency:
- Oil and gas a cheap, why not change it? More frequent oil changes are cheap insurance.
- The oil in a F650 is used for the gearbox, clutch and engine.
- There may be a trade-off against the risk of damage to the bike. For example forgotten O-rings and stripped drain plugs.
|Sample Oil Assay #1: Flash #412 on a Classic|
So I got real tired of being confused and worried about IF I can use Castrol Syntec 5W50 full synthetic oil in my '98 F650 and decided to DO something about it. Here is what I did... I took a sample of oil from a bottle from the same lot that I put in at the oil and filter change (Sample "zero-minus"). I slightly overfilled the bike when I changed the oil. I rode it about twenty or so miles to get it fully warmed up. I removed several ounces of oil and called that "Sample Zero-Plus." I had intended to pull several samples along the way. But due to circumstance in my life, didn't. I intended to run the oil for 6000 miles, per BMW's specification. But at 6000 miles I was not very far from Mena, Arkansas. So it had more like 7,000 miles on it when I drained it. I saved a sample of that oil, too. Then, after having samples of oil sitting around in my garage from September to November, I finally got off my duff and mailed them to Lubriport for an assay. The "zero-minus" baseline-sample is free. Because I specified that I'm in a couple or three BMW clubs, I got a discount. All told, they charged me $18 to assay the oil and give me what they call "Total Base Numbers."
About the fuel dilution in the report... as far as I know, the only way fuel gets into the oil is past the rings. I replaced my rings shortly before I changed the oil at the start of this test. I figure at the next oil change/assay, I should see a lot less dilution. (Or possibly something to think REAL hard about). Also, the assayer mentioned in another email... "One of our club members had similar fuel dilution and learned that it is sometimes a result of overfilling gas tank. As fuel expands it is pushed out of tank through fuel lines and can find its way into engine, even if not running. It was in one of the BMW columns on internet someplace." Now I am not sure I am buying this. I think his club member had "pukin' petrol syndrome." In any case, my plan is to become religious about turning off my petcock when I park the bike. And more importantly, remembering to turn it back ON when I depart on the bike.
AL went from 1.7 in the sample of oil that had never seen the inside of a motor to 2.5 inside a motor after about twenty miles. Seven thousand miles later, it was 90 parts per million. The assayer noted "Moderate aluminum wear occurring." I ain't exactly thrilled about that. But... what do you propose I do about it? Should I change to a different oil? What oil? Why? Do you have any evidence that supports the fact that some other oil will reduce this moderate wear?
The viscosity dropped by about one-third in 7000 miles due to fuel contamination. I ain't gonna worry about that since the assayer doesn't have anything bad to say about it. What I will do is see if extra time on the rings AND closing the petcock makes any difference for the next oil run. If the dilution doesn't come down, THEN I will start a deeper investigation.
- 30% loss of viscosity.
Caused by a 6% dilution due to fuel.
- Aluminum and iron floating around not captured by filter.
These are loose molecules measured in tens of parts per million, not chunks of stuff that CAN be trapped in the filter.
- Boron and molybdenum 10-20% reduced.
But not used up.
Basically, there are some things going on in my motor with which I am not thrilled. Because of the new rings and the abbreviated number of samples, I cannot de-convolve what is oil related from what is related to THIS motor. However, this study shows me that the oil holds up after 7000 miles. This study tells me that 5W50 Syntec isn't going to HURT my motor, even if I am a lazy SOB and run it WAY past 6000 miles. The oil in this study did some HARD service. 2000 of the 7000 miles was done in one weekend, on a run across Wyoming and Montana in August. 2000 of the 7000 miles was done in one weekend, on a run across Texas and Arkansas and then back across Kansas in September. 1000 of that was in a single day. At least 3000 of the 7000 miles were spent with the throttle mostly at the stop. Yes, that is not so great for a motor. Yes, I expect to see some wear associated with that sort of treatment. But what I FEARED was oil breakdown due to shear in the transmission and clutch. That CLEARLY is NOT happening. The metal stuff and dilution stuff... I believe that would be happening no matter what oil I was running.
|Sample Oil Assay #2: BradG#1002 on a GS|
- I put in Golden Spectro 4, a synthetic/dino blend, $6 a liter, at the 12K service. I sampled it at +300 miles. The report shows new and this +300 mile sample.
- For the record Golden Spectro 4: JASO MA standard as well as petroleum industry standards A.P.I SF, SG, and SH.
- So I did a side by side with Flash's report. Things I notice are:
The rest means little to me so I'll take Lubriport view that all is well. I'm not sure what to make of 20-30% differences when the values are in ppm. I'm thinking the real point is to spot changes from sample to sample that are significant. Just not sure I know what significant is in this case.
- Viscosity: GS4 20W50 starts out higher but mine dropped 20% in just 300 miles.
- Low metal levels BUT what is with the Magnesium, Zinc and Phosphorus levels? They must be additives in the oil because the levels in the new sample are higher than the used oil.
- My dilution at 300 miles is 2% on a FI bike. Not sure if carbs v. FI matters.
F650 Oil Choice
Ambiet Temperature and Oil Viscosity
- Please review the chart in the Oil Viscosity section. This chart contains the BMW recommended viscosity for FI models (GS, Dakar and CS) and the Carb models (Classic / ST). Note: These charts are based on "ambient" temperature (i.e. the air temperature).
- If you ride all rear round, and ride far more than the recommended service interval, you may want two different viscosities. For example, in winter in Canberra, temperatures range from -10C to +20C, and in summer they range from +10C to +40C. So I use an SAE 10W40 in winter, and a SAE 20W50 during summer.
SJ Oil Specification
- BMW Service Bulletin 2855 from 1998 states SJ specification oil is not suitable for BMW motorcycles. BMW says it does not guaranty the required levels of wear protective additives such as Calcium, Magnesium, Zinc, etc.
- As oil specifications are supposed to be backwards compatible, any oils released after SJ must also be compatible with SJ oil, and thus not suitable for use in BMW motorcycles. However BMW has released no known subsequent bulletins on the use of later specification oils, and it is suspected the BMW service bulletin about SJ oil is more a marketing campaign. To quote the service bulletin in question:
We suggest that you council with your customers regarding the oils being used in their motorcycle. Most oils found in commercial discount and automotive supply stores are now API SJ classification, which means that they should not be used. Use this opportunity to create instore displays and promote the full range of approved BMW motorcycle lubricants.
- Note: If an oil is an SJ spec, and it ALSO meets the SG or SH spec, then it should be okay to use (you will typically see SG/SH/SJ in the same place on the label).
- Perform a search on the Internet for "oil sj bmw" and start reading all the analysis performed by others.
- This is a big NO NO on the F650 and G650X. These bikes have a wet clutch and EC (Energy Conserving) oils contain friction modifiers that can be detrimental to wet clutches.
Synthetic / Semi-synthetic / Mineral Oil Debate
- Note: Many opinions have been removed from this section. If you have no idea if you should be using Synthetic oils or not, then just stick to standard mineral oil. So long as the mineral oil fits the specifications, you should be okay.
- If you choose to use Synthetic oils, the concensus is it is safest to wait until at least 6,000miles / 10,000kms before you start using them. Some people think waiting until 12,000miles / 20,000kms is best before you start using a synthetic oil. You do not HAVE TO start using a synthetic oil at any point - some people PREFER to.
- Many people have reported no problems using full synthetic oil and semi-synthetic oil in their F650.
- A few people have reported clutch slippage with synthetic oils. However it is usually the "friction modifier" that will cause clutch slippage.
- If anyone has the BMW bulletin regarding synthetic oil in motorcycles, please let us know so the specific details can be reviewed.
European oils use different additives because they have to meet European (ACEA) specifications that US oils do not. Any oil that meets the requirements listed in the bike's manual is good enough. Engine failure is rarely caused by oil failure, usually due to lack of oil or dirty oil. To paraphrase a previous thread: Fresh oil is better than Dirty Oil which is better than No Oil.
Synthetic vs. Mineral Oil
Back in 1998, Mobil filed suit against Castrol for falsely advertising Syntec oil as synthetic, when in fact it contained a highly hydroprocessed mineral (Dino) oil instead of a chemically synthesized basestock. Due to the amount that the mineral oil had been chemically changed, the judge decided that Mobil lost that suit. As a result (except in Germany), any oil containing this highly hydroprocessed mineral (Dino) oil (currently called Group III basestock by the American Petroleum Institute) can market themselves as a synthetic oil. Since the original synthetic basestock (polyalphaolefin or PAO) costs approximately 3 times as much as the Group III basestock, most of the oil blenders switched to the Group III basestock, which significantly increased their profit margins (the price of synthetic oils didn't drop, as I recall, to accommodate this cheaper basestock, which makes up >70% of a bottle of oil). In Europe, blenders still need to use some PAO in order to meet the toughest ACEA specs. In the US, Mobil 1, Amsoil, Red Line and Royal Purple are the only ones I am SURE OF still using PAO. If you can get a material safety data sheet (MSDS) for the oil you are interested in, look for PAO or polymer or oligomer of 1-decene as a component for a tip-off. Synthetic blends contain some amount (not defined, as far as I know) of synthetic basestock. The small amount of viscosity modifier present in most multi-grade oils probably fulfils this requirement, making synthetic blends another profit centre for the oil blenders.
PAO-based and mineral oil-based oils are compatible. There are a few synthetics that are not (these are ester-based oils, not suitable for or sold for everyday driving). Again, check the MSDS. However, there are at least 4 different companies that provide the additive packages that are blended into oils. Mixing these 4 different additive technologies can be bad (at least long-term). I am assuming that if you stay with the same brand/company's oil (Synth vs. Dino) there shouldn't be too much problem, but mixing oils is not a good practice.
There are 4 major PAO producers: BP Chemical (merchant supplier), Chevron-Phillips Chemical (merchant supplier), Neste (European merchant supplier), Exxon-Mobil (mostly internal use by Mobil). Of course, most of the big oil companies (and a few others) produce the highly hydroprocessed mineral (Dino) oil synthetic.
Group III (Dino) advantages
- Extremely good low temperature viscosity (in case you want to start your bike at -40C or -40F).
- Clean engine internals (downside: can also clean up crud from damaged seals in older engines, possibly allowing damaged seals to leak).
- Low volatility (have to top up oil less).
- More stable at extremely hot temperatures.
Regular engine oils
- Better profit margin for blenders, but can still be marketed as synthetic
- Meets minimum oil specifications (as do regular oils)
- Low volatility.
- May be better (in some cases) to break in a new/rebuilt engine
- Meet all warranty specifications (be sure to read your manual for specifics)
- Less expensive
- Less protection in EXTREME use
- There is a significant difference between US and European oils. Two different specs. Synthetic is only a marketing term in the US. Can contain massaged dino oil, OR chemically synthesized basestock (polyalphaolefin). Much lower margin on the PAO based stuff (ala Mobil 1, Redline, Amsoil) than the other synthetics. Can't image the profit margin on regular dino is very high...the Synth blends are high, the dino synths are too. The dino based synthetic oils should not be a problem to seals and mix with normal oil.
- The PAO based stuff usually contains a little ester, which is designed to swell the seals a bit to offset the little bit that the PAO shrinks them. Not so much a problem with new seal material, but a fix (that the old vehicles needed), which was one of the problems unsolved in the first synthetics back in the 70s. Problem with starting to use the stuff (with ester) on hi-mileage vehicles is that they do a thorough job cleaning out all the crud that had been keeping those worn seals from leaking, so then the seals would then leak. Newer oils don't let as much crud build up to damage seals, so probably less of an issue nowadays (but going back to cheap dino can't fix the cleaned leaking worn seals).
Upper-Cylinder Lubricants and Oil Additives
- The BMW FI models (GS,CS, Dakar and probably the G650X) handbook recommends AGAINST using upper-cylinder lubricants or oil additives.
- It is unknown if this applies to the Classic models (but it probably does)
- Which oil brand should you use? Whatever you like, so long as it is suitable within the above guidelines. Each person seems to have a different opinion on which brand oil you should be using, so specific brands are not identified here.
- The BMW GS Service sheet states "BMW recommends Castrol Oils".
- Do NOT ask what oil you should be using in the forums. This FAQ provides enough for you to work it out yourself. If in doubt, select a motorcycle oil that is consistent with the suggestions in this section.
Oil Circuit Maintenance
Oil Pump Removal
If someone can provide images for the following, that would be fantastic. These instructions are just a guide. More detailed instructions are also required.
- Remove the clutch cover, clutch and clutch basket. You should see two large black plastic gears (the oil pump gears), and one large white plastic gear.
- On the white gear, remove the retaining ring and the thrust washer from the mainshaft. Remove the white gear.
- Remove the retaining ring from each of the black oil pump gears. Snap the oil pump gears out upwards. Remove the needle pins from the oil pump shafts.
- Remove the thrust washers. You should now be able to see the cover for the oil pumps.
- Remove the 6 screws from both oil pump covers. Note: These screws are listed in the BMW GS manual as using Loctite 243, and torqued to 6Nm.
Oil Pump Wear Limits
Use a set of feeler guages to check the inner and outer rotors for clearance. Note: These values are from the Rotax 655 manual.
- Clearance between inner and outer rotor: max. 0.25mm
- Clearance between outer rotor and crankcase: max. 0.25mm
- Axial clearance between rotors and cover: max. 0.20mm (according to the BMW GS manual, this should be 0.25mm)
- Check running surfaces of oil pump rotors in crankcase and oil pump cover for scores.
- Inner diameter of oil pump gears: max. 14.20mm
- Retaining groove of two oil pump gears: max. 3.7mm (this is the groove in the oil pump gear that snaps onto the pin that holds it in place).
Bleeding the Oil Circuit
You should only need to bleed the oil circuit if you have split the crankcase for maintenance. (If anyone has pictures of this process, please let us know, or post images in the Forums).
- Remove the oil filter (GS Oil Filter Cover or the Classic Oil Filter Cover).
- On the bottom right (at about the 5 o'clock position) there should be a check valve. Remove this. (Anyone have any pictures?)
- Remove a spark plug.
- Turn the engine over until oil emerges at the filter chamber.
- Re-install the check valve, oil filter and filter cover (but NOT the spark plug).
- Turn the engine over until oil comes out of the oil return line.
- Re-install the spark plug and run the engine for a few minutes.
- Check the oil level as specified in the oil change FAQ for your bike.
Misc Oil Questions
Can I get more power from a different oil?
- Cheap HP? My son and his co-workers were bored on Monday, so they figured they'd do a little test. A customer's KX900RR or something was in for an oil change and the owner was asking about Synth. They did the change with Motul 10-40 dino, and ran it on the dyno. Then they drained it and put in Motul Synth Blend, then once again with Motul fully synthetic. With the baseline of the dino, the semi ran +2hp and the fully Synth ran +5hp in 50% of the power band. As my son pointed out, that's the equivalent of a $300-400 re-jetting or a $1000 pipe. YHPMV. David #476, '99 F650, Las Vegas, NV.
- If anyone has conducted such a test on an F650, please let us know the details, and if you can get the dyno output so we can include it in this FAQ.
Do some oils result in the clutch slipping?
- First check your clutch adjustment.
- One of the most likely cause of a slipping clutch is the use of EC (Energy Conserving) rated oil. Stop using it. It may take several oil changes before you experience fewer problems.
- If you did not have a slipping clutch before changing the oil, and you now have a slipping clutch, look closely at the new oil you have used, and consider changing it to something else.
- See the section about EC Rating and the Synthetic Debate.
- If you have had a slipping clutch for a long time, you may need to replace the clutch. As far as waiting for destruction goes, its unlikely the clutch failure will damage anything else. However if it goes suddenly you may be left stranded and worst of all you may suddenly loose drive. If this is during a wet corner, it will be unpleasant to say the least.
- If it still slips AFTER you change the oil and are sure the clutch is adjusted properly, THEN look into replacing the clutch pack. Though you might be able to get away with soaking the plates in lacquer thinner and reusing them after giving them a light surface sanding with about 320 or 400 grit emery paper.
Can I add an oil cooler to my F650?
What if I do not drive more than 6000miles/10000kms in a year?
- NOx (Nitrous Oxide) from blow-by residing in the oil combines with water to form nitric acid which eventually overwhelms the additives included to neutralize such nastiness. The nitric acid then begins to etch your various bearing surfaces, which will wear quite a bit more rapidly than they will in an engine with regular oil changes. Basically... fresh oil is cheap insurance.
Can I mix different oil types?
- As a general rule of thumb, no. Depending on the oils, it is unknown how the different components of each oil will react.
- If you must mix different oils, try and stick with the same viscosity, specification and brand. For example if you have 10W40 and 10W50, both of SG specification from the same manufacturer, it might be okay. But if you had 20W50/SG and 10W40/SH from two different manufacturers, it would probably be a bad idea.
- Remember: Clean oil is better than dirty oil, and dirty oil is better than no oil.
What is this white gunk under my oil cap?
- In colder climates, water can condense inside your engine and oil tank. This is particularly noticable if you take lots of shorter (less than 20miles / 32kms) trips. On shorter trips, your oil does not heat up enough to aid in evoporation of the water in the oil. As a result you end up with white-ish gunk under your oil cap.
- This could also be a sign of a failed water pump. Check the Water Pump Seal Repair FAQ for more information and symptoms.
Should my oil look like a mocca coffee?
- As a general rule NO. However check the Water Pump Seal Repair FAQ for more information on failed water pumps, and for symptoms of failed water pumps.
My bike is overheating. Could oil be the problem?
- Oil does help in the cooling of your F650. On the fuel injected models, the oil tank has fins on it to aid in cooling the oil. For more detailed information on overheating, see the Overheating FAQ.
What do I do with my "used" oil?
- Do not poor it down the drain
- Do not poor it on the garden
- Do not throw it in the bin
- Talk to your local mechanics - they may be happy to take the oil for you and throw it in their general "used oil" bucket - which should then be sent for recycling.
Can I use SK... SL... oils in my bike?
- In theory, later oil specifications are required to be backwards compatible with earlier specifications. This an oil specification of SL must be backwards compatible with SJ oil. BMW states you should not use SJ specification oil in your BMW motorcycles. So in theory you should not use these specification oils.
- See the SJ Oil Specification debate for more information.
Should I soak a new oil filter before installing it?
- YES. By soaking the new oil filter before installing it, it will take less time for the fresh oil to reach the engine. If you simply insert the new oil filter, when you first start the engine, it will take a second or two for the oil to fully soak into the filter.
- The other alternative is to turn the engine over a for a few seconds before starting it with the fresh oil. On the GS this can be done by placing the bike in gear, pulling the clutch in, the sidestand down and pressing the starter button.
How do I get an oil assay done?
- In the US try Libriport:
1650 Airline Drive
Kenner, LA 70062
- Here's the deal... take a look at the oil report to get an idea of what-all you should tell them and what-all you'll get back. They would LIKE four ounces per sample, but can make-do with less. They PREFER small glass containers. Baby food jars make EXCELLENT containers. Plastic containers are ok. But don't put hot oil into them. Be sure to put the containers in zip-lock bags and use some packing material so that they don't get broken in shipping. Clearly mark all the samples as to what they are. You can see on the report stuff that you want to tell them... what year and model vehicle it is from. The date the sample was taken. The mileage of the vehicle at the time of sampling. The mileage on the OIL at the time of sampling. They WILL keep records and look at them for trends if you just send samples at the oil change each time. It is BETTER if you can catch the oil as it drains from the motor BEFORE it hits the catch pan. But that isn't critical. If you send a sample of FRESH unused oil, be sure to state the brand, product, weight and LOT NUMBER FROM THE CONTAINER. That base-line sample is FREE. It is $9/sample for the used oils, at the BMW-club discount price.
- Write a letter and put it in with the samples. Tell them you're in whatever BMW club(s) yer in. Give them your name, address, credit card number and exp date and an email address. They'll hit your card for the dough when the assay is done and email the report as well as snail mailing it to your address. As I mentioned previously, their turn-time is REAL fast. Shipping the sample there takes a lot longer than the assay.
- Disclaimer: The Chain Gang is not associated with Lubriport in any way, other than some CG members have used Lubriport in the past.
What is it again that is aluminum and wears inside the engine?
- Oil assays show increases in aluminium in the oil over time. What is it that wears inside the engine to create this increase? It that the coolant pump shaft or the clutch actuator? You would think that all rubbing parts would be made of real steel. I can see the piston wearing a bit, like you mention. That Nikasil coating is going nowhere, so I guess any wear must have to come off the piston at the usual piston skirt wear spots. And I know clutch baskets wear when they slide against each other. Hopefully, that covers about all of the sources of aluminum wear in an engine.
- The clutch hub, which probably doesn't get too much wear, and outer retainer, which spins against friction disc and probably does. The cam/head interface. Piston.
- The shim buckets rubbing against the walls of the bore they ride in.
Do additives (Zinc, Phos and Moly) make motorcycle oils more expensive?
- Yes and no.
- Zinc, Phos, and Moly are extreme pressure additives. They "activate" at different temperatures, so the combination gives you protection at all normal operating temperatures. Calcium (and likely magnesium as an "impurity") are in there as carbonates to neutralize acids formed during combustion (Richard, certain forms of calcium carbonate, I.e. platelets, can also double as a quasi-EP additive). Boron is part of a borate compound, but I have forgotten it's purpose (rust & oxidation inhibitor?). Silicon can be a sign of poor air filtration (dust is silicon dioxide), or from the defoamer used in the oil (usually silicone/siloxane), or as part of an aluminum alloy (usually 5-10% in pistons). Most of the other metals are wear bits from the engine...tin, lead and silver tend to come from bearings, chrome and nickel from chrome plated items (piston rings?), copper from bearing cages. As was said, the good things tend to go down in concentration, the wear things tend to go up (if applicable...I doubt that BMW used silver bearing bearings in the F650, so that one will likely stay flat). These are sometimes called "trending analyses" just for that reason. Disclaimer: these are just guidelines done from memory, so the usual caveats apply.
- The additives themselves are not expensive. But their levels have been consistently reduced in car oils over the years. They are necessary for the transmissions found sharing motorcycle engine oil. So what you have is a case of motorcyclists being on the short side in the supply/demand game. Since the cages no longer demand significant quantities of these additives, major suppliers don't put them in the cage oil. But since motorcycles DO demand them... an opportunity to gouge the motorcyclists was born. And motorcycle-$pecific oils were created. You take a car oil that retails (list) for $1.89 and add a half penny worth of trace metals to it along with a label that has a picture of a motorcycle and VOILA, you now have $4.99 "worth" of oil. It gets worse with the synthetics.
THIS was the whole reason for doing the assay in the first place. If we, TOGETHER, assay a whole bunch of CAR oils and MOTORCYCLE oils and SHARE our results, we may be able to show that the emperor is indeed nekkid (and trying to screw us). Then again, we may show that motorcycle oils are actually required and using car oils is penny wise and pound foolish. Or... perhaps we will prove a need and some enterprising person will create a company that provides a motorcycle-specific additive-package for car oils at a reasonable price. I'd happily pay $0.99 for four cents worth of chemicals to add to my two $4 quarts of "synthetic car-oil" at oil-change time instead of paying $16 for two quarts of synthetic oils "designed for motorcycles." But, until we have DATA, we will never know.
At $9 per assay, I could easily afford the car oil a whole faster than I can afford the survey of the wear characteristics of ALL the oils out there. So, I did the first test and learned that Castrol Syntec 5W50 ("car oil') functions just fine in a Rotax single, even after 7,000 miles. I also learned that my motor has some higher levels of aluminum in the oil, which may or may not be related to fairly new rings. And I learned that my oil suffers from fuel-dilution, which may be contributing to the higher levels of aluminum. So, I am repeating the assay, with more data points on a better broken-in engine and turning off the petcock when I park.
If everyone with a strong opinion about their oil would just put $9 of their money where their mouth is, then we would have a fantastic amount of DATA instead of mere conjecture, religion and oil company hype & F.U.D. Please, Everyone, the next time YOU change your oil, send a sample in for assay and post the results along with the brand, weight and number of miles on the oil, plus any relevant comments. Thanks!
- To add to Flash's comments... The phos additives in the oil are being reduced as the government forces the car manufacturers to warranty their emission equipment (I.e. cats) for longer mileage. Not an issue in my case, as the cat rusted out and fell off at 90K (on cage) ...but the phos poisons the catalyst very slowly (100K, 120K, 150K?). To compound this, the phos is part of a cheap additive called Zinc DialkylDithioPhosphate (aka ZDDP)...so when you reduce the phos, you also reduce the zinc (both antiwear additives). When does a phos content dropping from 0.12 max to 0.10 max to (proposed) 0.08 or 0.05 max become a concern? Much a subject of debate...currently the auto manufacturers want the NEXT version (SM?) of oil to be NON-BACKWARD COMPATIBLE (i.e. REALLY low phos/zinc)...while others DON'T (twice as much to inventory/stock, not to mention potential for screw ups, which more or less acknowledges that it may cause problems in older cars (and bikes?)). Japan, INC is so concerned about low-phos motorcycle oil that new categories (MA and MB) have been developed especially for motorcycle engines. Unfortunately, it is unlikely that any lowly car oils will get this "extra" certification, as long as their higher priced motorcycle $PECIAL oils can be marketed using it. The Mobil 1 motorcycle oil contains slightly more ZDDP than the automotive version (verified by MSDSs). The trend of the future looks to be toward motorcycle specialty oils exclusively. As for Flash's idea of adding extra additive...it would work, IF you knew WHICH additive to add, and had a source for it. There are at least four additive companies in the US, each selling many additive packages different enough to steer clear of each other's patents. Which one to use in which oil? BMW's solution to this may be really unique, as they will have to deal with the catalytic converter issue AND the wear issue. Non-phos containing antiwears are available, but much pricier. Not to discourage the project, but my guess is that a lot of this analysis will be for naught (my test will be on SJ-rated Mobil 1 for cars, which already is no longer available). New oils are due in 2004 (whether or not they meet this timetable with the current stand-off is yet to be seen), so the oils surveyed in 2003 may be unavailable by sometime in 2004. If you participate in the study, please be specific about the type of oil tested, including the viscosity grade and all the API designation (SG, SH, SJ, SL, CH-4, CI-4, MA, MB, ACEA, etc.). Some oils list MANY of these on the same bottle.
Should I worry about fresh oil turning dark quickly?
- No. Fresh oil is very clear. Almost everyone finds their fresh oil will become dark very quickly (sometimes after less than a few miles). This is perfectly normal.
What temperature should my oil be?
- Hotter than boiling water and cooler than the temperature at which the oil starts to break down. Basically, 101°C (214°F) to about 110°C (230°F) is best.
Person A: So what oil should I use?
Smartarse 1: Baby oil
Smartarse 2: Coconut oil
Smartarse 3: Massage oil, and don't forget to rotate your blinker fluid ;P
[Ed note: Do not use any of the three oils just suggested, and if you do
not know how to rotate your blinker fluid, please ask in the forums].