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Oil, not just another thread

daboo said:
My thoughts exactly. If it has oil in it and a failure occurs, unless it comes out like molasses, they won't look further.

As I'm reading this, I'm just wondering and trying to apply a bit of logic. From what I've read, the most wear on the engine occurs in the first seconds of startup when the oil has drained. So to get the oil to the places that need it, a lighter weight oil is better than a heavier weight oil.

Now once the engine gets running, does it care what the outside temperature is? Maybe in Fairbanks in December. But for most of us, I'm not sure it matters after a minute or two. Parts are moving on bearings and everything is heating up quickly.

After a few minutes, the engine is at full operating temperature. It's hot. Really hot. From what I've experienced, it doesn't matter if the outside temperature is 35F, or 105F, if I'm in stop-n-go traffic, the fan will eventually kick in...indicating the engine and everything inside it, is hot. At 105F, obviously the fan kicks in more often...but it never overheats.

So my point in this long-winded post is I don't know that our rationale for using heavier weight oils on a water-cooled engine really is valid any more. On an air-cooled engine, yes. But as long as the fan is working and the engine temp doesn't exceed the normal operating temperature...the engine oil really doesn't know what's happening outside the engine. The heat inside the engine is far greater than anything outside of it...and the radiator and cooling system is doing what it is designed to do...maintain the engine temperature at the optimum for performance and emissions.

I think you need to find another cure for your noisy engine. STP was the answer back when I was growing up. Of course the oil was incredibly thick and could be compared to molasses...

Chris
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I'm running an oil cooled 2012, so the mechanic probably knows of what he's talking about in the desert heat here. In any event, I'm following his lead, he's the experienced mechanic who works on a lot of GS's, not me.
 
Personally, I take my oil advice from the owner’s manual ...

Which in my case is "SAE 5W-40, API SL/JASO, Additives are prohibited because they would attack the coatings on engine components." This one oil spec is for all operating temperatures.
 
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I agree that outside temperature has less effect on the engine temperature on the water cooled motor, but it does affect it to some degree. I can see this on the temp reading on my GPS when the bike is running at idle or slow speed so that there is less air flow over the radiator.

However, the clacking starts after the engine has been run for a length of time regardless of the outside temperature. Outside of the unpleasantness of the noise, the motor runs perfectly fine. There is no apparent negative affect on fuel mileage or acceleration. In fact, once underway, the motor doesn't even seem loud. It is only at idle.

Is this really a problem that needs to be solved?
 
I thought the wet heads valves were actuated directly on the cams through a semi spherical shim? How will thicker oil quiet them down?

Are the cam chain tensioner's on the wethead hydraulic? Is the noise you are hearing?
 
daboo said:
... I don't know that our rationale for using heavier weight oils on a water-cooled engine really is valid any more. On an air-cooled engine, yes. But as long as the fan is working and the engine temp doesn't exceed the normal operating temperature...the engine oil really doesn't know what's happening outside the engine. Chris
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Chris' well-reasoned response has me scratching my head. Two memories: I used to play with antique airplanes, all of which had air-cooled engines with very sloppy clearances compared with modern wet ICEs. One of them had a really old, really tired motor which ran incredibly smoothly as all old engines do just before they die. I finally decided to overhaul it because at summer operating temps I could see the oil pressure dropping quite a bit - an indicator of wear the viscosity was not capable of filling. (In winter the pressure also dropped but only a little.) Fast forward, I had a 1999 BMW M Coupe which had the S54 in-line six, as smooth an engine as was ever built. However, the car was not designed with an auxiliary oil-cooler. (The follow-on model rec'd one.) In the SW desert summer heat, the oil was always pegged at 240°F (or more - that's just as high as the gauge reported). So while I agree with Chris the temperature inside an engine is pretty high regardless of ambient air - typically in a gasoline ICE, the top ring is around 212°F - the water radiator's ability to control oil temps has limits. At some point, as BMW determined with the car, you either need to add more oil cooling capacity or raise its viscosity endurance or both. I also agree with Chris there are huge differences between air-cooled and H2O-cooled motors. One of the reasons BMW introduced the H2O-cooled motor was so they could shrink the clearances and achieve better emissions numbers and MPG. The smaller clearances obviously affect cold-engine oil viscosity requirements, hence 5W. (Some new Hondas have gone to 0W.) 5W-40 is probably a good one-size-fits-all benchmark for BMW to recommend for wetheads. But if I sat down with one of their engineers over beers at Oktoberfest and asked off-record what s/he thought about 20W-50 in the desert SW during prolonged 100°F+ heat, I'm guessing if I received an answer at all it would fall along the lines of das ist gut.
 
Wethead said:
my 2018 seems to be making too much noise to me: like a clacking of valves
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I think it's the injector actuators causing this noise that is reflected off of fairing parts on wethead RTs. I think the solution is to use good quality earplugs correctly inserted, which will also help preserve your hearing. I listen to music regularly thru a Sena 10R and volume and tone quality is very decent despite going thru ear plugs. I seriously doubt using 20w50 oil could possibly hurt a thing especially in your hot climate. One thing that may help reduce wear is to do a nice slow warm up when you start up cold. I typically keep RPMs under 2400 and take it real easy for the first mile or so of riding just to give things a chance to get fully lubed and warmed up.
 
Nice to see some constructive posts :thumb

I'm due for an oil and filter on the F800GS. I have found that after it sits a bit there is a brief noise/clatter/run dry sound that happens occasionally. I don't think the noise really means anything and or hurts anything but I'd just as soon alleviate it- if I can. At the next change I plan to use one of the additives I use in some of the other 20 or so engines that don't run as frequently as the engines that run daily.
OM
 
I was curious as to what effect, if any, going to a thicker oil would do.
I found this opinion letter that explains oil viscosity, thickness, mineral vs synthetic esther oils and resistance to higher temps.
It also explains what the benefits may be and also the risks. And it also talks about what application, where they would recommend a heavier grade oil.

It's a good read https://www.opieoils.co.uk/t-car-engine-oil-10w-60-explained.aspx
 
ncpbmw1953 said:
I think it's the injector actuators causing this noise that is reflected off of fairing parts on wethead RTs. I think the solution is to use good quality earplugs correctly inserted, which will also help preserve your hearing. I listen to music regularly thru a Sena 10R and volume and tone quality is very decent despite going thru ear plugs. I seriously doubt using 20w50 oil could possibly hurt a thing especially in your hot climate. One thing that may help reduce wear is to do a nice slow warm up when you start up cold. I typically keep RPMs under 2400 and take it real easy for the first mile or so of riding just to give things a chance to get fully lubed and warmed up.
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This might be a good explanation. When I moved from Eastern Oregon to the coast I noticed a fairly loud ticking noise or noises coming from the the left cylinder bank top end on my 2011 Mustang GT/CS so off to the local Ford dealer. Turns out the noise was indeed coming from a couple fuel injectors. The shop foreman says this fuel injector noise is common to this area but not so much inland and he doesn't know why. When I heard this I thought BS but it turns out he was correct. Could be the much lower elevation coupled with lower air temperatures with higher humidity or who knows but for sure the ticking noise is fuel injector related. Oh, and this shop foreman knows his way around cars which is somewhat rare in today's dealer shops, imo, be it motorcycle or auto dealers.
 
Wow! thank you much for all the conscientious posts. I really appreciate it.

FYI, I had the valves checked in case the clacking was a lose one and they were all in specs.

After filtering all the interesting perspectives on this issue, I 'm leaning toward patience, and sticking with the 5--40 (particularly after reading the article posted by patm).

I 'll rethink this around 6k and maybe try a 20-50. But really, I have a vague memory of trying this out already on one of my earlier RT. This 2018 one is my fourth.

The problem is that I never run them down until they expire; I been trading them for the newer one like a consumer-sucker-for-the-new-model that I am. It would be interesting to run one down till something breaks inside and then take the engine apart see what went wrong. On the other hand, I neither have the patience nor the mechanical savvy for that.

Thank you all for making this a thought-provoking thread--and an oil-one at that.
 
I found this comment from patm's link interesting...

The thicker viscosity oils lead to a slower oil flow rate, which can lead to several problems. There can be localised high oil pressures in the engine, causing increased wear at certain points as the oilways are not designed to cope with the thicker oil. One of the main functions of the oil is to carry heat away from the engine and that is then cooled by the air flow over the sump – with the thicker oil the flow rate is slower, meaning less heat is taken away and higher oil temperatures occur (that can also lead to people thinking they need thicker oils). In a worst case scenario with thick oils (when not required) is that you will experience air entrainment and cavitation inside the bearings at high RPM. Not clever stuff!
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Chris
 
jandhumphreyme said:
I thought the wet heads valves were actuated directly on the cams through a semi spherical shim? How will thicker oil quiet them down?

Are the cam chain tensioner's on the wethead hydraulic? Is the noise you are hearing?
Click to expand...

The cam chain tensioners are hydraulic in oil head, hex and cam-head as well as wet-head. The shims in the wet-head are regular flat shims.
 
WETHEAD doesn’t Castrol make a 10-50 that meets Bmw specs, that may solve your problem
Just saying
 
t6pilot said:
WETHEAD doesn’t Castrol make a 10-50 that meets Bmw specs, that may solve your problem
Just saying
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I think this one meets BMW's JASO MA-2 spec for H2O-cooled R1200 engines - Castrol POWER1 Racing 4T 10W-50

https://msdspds.castrol.com/bpglis/FusionPDS.nsf/Files/0A2E52548039B38D80258210003445D2/$File/BPXE-AUW7S8.pdf
 
brownie0486 said:
I'm running an oil cooled 2012, so the mechanic probably knows of what he's talking about in the desert heat here. In any event, I'm following his lead, he's the experienced mechanic who works on a lot of GS's, not me.
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If that mechanic had a degree in chemistry or petroleum engineering or mechanical engineering, he'd have a better job. Otherwise, he's not an oil expert.
 
While BMW has improved the Wethead transmission, they were initially pretty insistent on use of full synthetic 5W-40 in wethead engines (with wet clutch, obviously).
 
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