Official S65 Rod Bearing Condition Example Thread

[serranot]

So, the BE naysayers complain there is not enough data to support BE's conclusions, and then to support their conclusions, they cite to one set of BE bearings with wear and one set of VAC without.

How can one, with a straight face, say that BE needs more data to prove their conclusions and then cite to two bearing sets to support that conclusion? Or cite to the fact that you used VAC and your engine runs good, therefore they are both equivalent options?

False equivalence. BE=using a pile of measured data + industry standard = a working theory. You=I used VAC; or "I took apart one engine=BE is wrong and I'm right.

I'm not biased because I chose BE; rather, I'm biased because BE is the ONLY group who chose to publish real data. Rather than spouting conclusory statements like "they're biased," cite to some evidence or data that proves it.

[Sneaky Pete]

Originally Posted by pbonsalb

You suggest most car makers now specify rod bearing clearances similar to what BMW used on the S65. Which of those car makers also specifies 10W60 oil?

Clearly BMW were well aware of the downsides of using a 10W60 weight oil with their RB clearance...they put in a (rarely seen) system on the rev counter to dissuade owners from using high rpms at cold temps.
Which in itself goes to support the premise that BMW made a conscious decision to stick with the S85s RB clearance when they were R&Ding the S65...rather than it being a mistake made by the tea boy.
That many owners likely paid scant attention to the need to warm up the oil only compounded the problem.
Myself I think the Rev counter system was inadequate and a more positive effort should have been made to counsel owners about not using high revs with cold oil. A colour coded oil temp gauge would maybe have been a better choice.

[doogee]

Originally Posted by serranot

So, the BE naysayers complain there is not enough data to support BE's conclusions, and then to support their conclusions, they cite to one set of BE bearings with wear and one set of VAC without.

How can one, with a straight face, say that BE needs more data to prove their conclusions and then cite to two bearing sets to support that conclusion? Or cite to the fact that you used VAC and your engine runs good, therefore they are both equivalent options?

False equivalence. BE=using a pile of measured data + industry standard = a working theory. You=I used VAC; or "I took apart one engine=BE is wrong and I'm right.

I'm not biased because I chose BE; rather, I'm biased because BE is the ONLY group who chose to publish real data. Rather than spouting conclusory statements like "they're biased," cite to some evidence or data that proves it.

I wasn't aware there even are any BE "naysayers". Who is asking for more data?

Just because BE chose to publish data, does not make them a better choice. VAC has been in this business a long time and clearly doesn't care to spend time to do the same. Doesn't mean it's an inferior product.

I simply chose VAC because of their experience and actual real world use in other engines.

I don't think anyone in here has claimed BE Bearings are no good or anything along those lines? Maybe I missed a section.

You BE guys take everything as an attack. I'm just sharing information to benefit everybody.

[serranot]

Originally Posted by doogee

I wasn't aware there even are any BE "naysayers". Who is asking for more data?

Just because BE chose to publish data, does not make them a better choice. VAC has been in this business a long time and clearly doesn't care to spend time to do the same. Doesn't mean it's an inferior product.

I simply chose VAC because of their experience and actual real world use in other engines.

I don't think anyone in here has claimed BE Bearings are no good or anything along those lines? Maybe I missed a section.

You BE guys take everything as an attack. I'm just sharing information to benefit everybody.

I'm not a "BE guy." I'm someone who bought their product.

I'm not being critical of people who bought something else. I suppose "real world experience" is data. It's just not quantifiable to the same extent measurements and numbers are.

What I am saying is that I don't view "real world experience" as comparable to BE data. While it could be that, I suppose, after a time, those three words without names and engines and people is not data to me.

Believe it or not, I *do* try to understand other perspectives. For me, it's like the intelligent design movement. Comparing scientific experiments to "the world is just so amazing it must have been created by God" is not a logical comparison. It's just a conclusion based on how one has to have things work based on one's beliefs. So, when someone says "I bought VAC because of real world experience" and compares that to buying BE because of data measurements and the like, it just doesn't work for me. But at the end of the day I don't care what one buys. I just bristle when one treats that as a data comparison it (in my opinion) isn't.

[doogee]

Originally Posted by serranot

So, when someone says "I bought VAC because of real world experience" and compares that to buying BE because of data measurements and the like, it just doesn't work for me. But at the end of the day I don't care what one buys. I just bristle when one treats that as a data comparison it (in my opinion) isn't.

I never claimed it was a "data comparison".

When I had seen multiple sets of VAC bearings pulled with a reasonable amount of mileage and no wear, that was clearly a no-brainer for me vs taking a chance on some numbers a company posted on the internet with no real world testing.

If at the time, BE had the data and some examples, I would of chosen them hands down. But it was far too early for any of that.


Lets get back to the threads purpose. Hopefully we'll soon be getting examples from motors that have already had bearing swaps.

[serranot]

Originally Posted by doogee

I never claimed it was a "data comparison".

When I had seen multiple sets of VAC bearings pulled with a reasonable amount of mileage and no wear, that was clearly a no-brainer for me vs taking a chance on some numbers a company posted on the internet with no real world testing.

If at the time, BE had the data and some examples, I would of chosen them hands down. But it was far too early for any of that.


Lets get back to the threads purpose. Hopefully we'll soon be getting examples from motors that have already had bearing swaps.

That's fair and makes sense.

[Sneaky Pete]

Originally Posted by serranot

What I am saying is that I don't view "real world experience" as comparable to BE data.

And what is it that you think the "BE data" proves?
Anyone can take a data set and suggest a theory that supposedly fits that data...it doesn't mean that the theory is correct.
Especially when it requires so many logical contortions (or even to abandon logic altogether) to satisfy the data.

[Bartledoo]

Originally Posted by Sneaky Pete

Clearly BMW were well aware of the downsides of using a 10W60 weight oil with their RB clearance...they put in a (rarely seen) system on the rev counter to dissuade owners from using high rpms at cold temps.
Which in itself goes to support the premise that BMW made a conscious decision to stick with the S85s RB clearance when they were R&Ding the S65...rather than it being a mistake made by the tea boy.
That many owners likely paid scant attention to the need to warm up the oil only compounded the problem.
Myself I think the Rev counter system was inadequate and a more positive effort should have been made to counsel owners about not using high revs with cold oil. A colour coded oil temp gauge would maybe have been a better choice.

To be fair, any argument made that BMW could have easily changed the bearing specs from the S85 to the S65 is completely disregarding the legal implications of such a fundamental design change. If they did make a significant bearing design change for the S65 and a class action suit was filed for the S85 owners, then how do you think the outcome would be affected? Engineering isn't always primary driving force in scenarios like this unfortunately.

So, regardless of which "side" is correct with regard to the ongoing bearing saga, you can't necessarily make that argument.

[doogee]

Originally Posted by serranot

That's fair and makes sense.

Woohoo I like ending things on a good note!

Originally Posted by ksteckba

To be fair, any argument made that BMW could have easily changed the bearing specs from the S85 to the S65 is completely disregarding the legal implications of such a fundamental design change. If they did make a significant bearing design change for the S65 and a class action suit was filed for the S85 owners, then how do you think the outcome would be affected? Engineering isn't always primary driving force in scenarios like this unfortunately.

So, regardless of which "side" is correct with regard to the ongoing bearing saga, you can't necessarily make that argument.

Agreed.

BMW knew exactly what they were getting into. They would have had plenty of data on S85 failures.

They haven't made any revisions to the bearings to save their own butt.

The bean counters run this side of the show.

Spitting out an engine with identical connecting rods, bearings, etc is far more economical. They would have saved a fortune on R&D. Instead electing to eat it by replacing a few motors under warranty and then washing their hands once these cars are out of warranty.

[Duk996]

Originally Posted by doogee

Agreed.

BMW knew exactly what they were getting into. They would have had plenty of data on S85 failures.

They haven't made any revisions to the bearings to save their own butt.

The bean counters run this side of the show.

Agreed, this isn't rocket science, they know exactly what went wrong back at HQ. It's dealing with the "what to do now" that is tricky.

Hopefully the class action suit brings some truth.

[IanMan]

Right, so if there wasn't a clearance issue then BMW just happened to release larger bearings for the S85 & S65 with a bigger clearance. Hmmmm......


Also funny is that Doogee is just using one example of poorly installed BE bearings compared to VAC bearings. For all we know is that the VAC bearings were not hammered on at all. I've talked to many people who have used BE bearings and were happy with the results and wear.

[serranot]

Originally Posted by Sneaky Pete

And what is it that you think the "BE data" proves?
Anyone can take a data set and suggest a theory that supposedly fits that data...it doesn't mean that the theory is correct.
Especially when it requires so many logical contortions (or even to abandon logic altogether) to satisfy the data.

No, anyone can't. Exactly what logic has been abandoned?

So far you and some others have argued that BE's data is faulty because it is a small sample size or because the data could point to other things.

That could be true, but it doesn't disprove their data. Again, I point to the theory of evolution and intelligent design. Evolution has been proven through the scientific method. The fact that there are some unknowns does not render evolution invalid nor does it mean that God created the universe. It means there are holes and that the theory is valid unless and until other data disproves the theory. Your assertion that BMW engineers did everything for a reason and they must have done it for good reasons belies the fact that the bearing are failing. Who cares whether they did something for a good reason or not? If it fails, intent is irrelevant.

BE has a working theory supported by its data. If a bunch of BE bearings show wear upon disassembly, that would be a good indicator that their working theory is false. But we don't have that. Yet.

With other manufacturers, we have some evidence that their solution works, but it's not a big sample and there is no explanation why it works. AND that manufacturer has also adopted the bigger clearance as a solution. They did that for some reason. Maybe it was to sell more bearings. Maybe it was for a technical reason. The point is I don't know. And given the two options, I went with option 1 because their data-based solution is more comforting to me than no data.

[oldmanstyle]

Originally Posted by ham_sammich

You can hate me all you want, until I see a larger engine sample size backed with consistent data, I'm a skeptic.

I don't hate you. I just think your approach here is unproductive because you have no legitimate counter to the information that has been presented. You're operating on uncertainties and doubts that are more unfounded than the ideas you are rejecting.

Originally Posted by ham_sammich

I'm a skeptic.

So are flat earthers.

[Green-Eggs]

Originally Posted by ham_sammich

To me, the wording used to describe each bearing example is biased to BE being the end all solution, to a problem no one has solved. I'm still waiting for one of these master engine builders to show proof of their clearance stacking theory. If it's out there, I'd like to see it.

You bring up a good point. I'm sure Bert would put whatever verbiage on the wiki page if VAC wanted to provide it. As it stands, they haven't. So I'm going to suggest Bert use VAC's own language found on their facebook page used to describe their own bearings.

VAC Facebook page says:

"Out with the old in with the new S65 Rod Bearings been replaced by VACMotorsports extra clearance bearings...These bearings will give an additional 0.0005" clearance to the OE bearing size. So with the coated bearing shells you will have the OE clearance. Some people have concerns about running Coated OE bearings so this is the fix for the concern."

The big take-away is that VAC calls them extra clearance in the announcement itself in February 2015, but then explains they are only extra clearance before the coating is added. Once the coating is added, according to VAC, they are OEM clearance. This should put an end what people are saying about them being extra clearance -- when in fact they're not designed to be extra clearance once the coating is added. It should put an end to this...but I'm sure it won't. So here's a screen shot to confirm nothing here was misrepresented.

Originally Posted by doogee

Once again you're telling people VAC bearings are something that they are not.

See above.

Maybe English is your second language and you don't quite understand. I'm not sure.

Whoops. See above.

Originally Posted by Dave07997S

The newer VAC Clevite bearings are extra clearance bearings. It was the older ones that were just coated..

From VACs website..

See above. According to VAC FB page at the time they announced the new bearings, they are extra clearance BEFORE the coating is added. Multiple people have called VAC and depending on who you talk to, some get this same answer even today. It's not extra clearance after the coating is added.

[Duk996]

Originally Posted by oldmanstyle

I don't hate you. I just think your approach here is unproductive because you have no legitimate counter to the information that has been presented. You're operating on uncertainties and doubts that are more unfounded than the ideas you are rejecting.

So are flat earthers.

I hate him. Most interactions with da sanich are contentious and unproductive.

[Scharbag]

Originally Posted by oldmanstyle

So are flat earthers.

Hold on, hold on. The earth is pretty flat up here in the prairies!

[Green-Eggs]

Originally Posted by ham_sammich

I'm still waiting for one of these master engine builders to show proof of their clearance stacking theory. If it's out there, I'd like to see it.

The information is already there, but obviously you can't measure the clearances on an engine that already blew up with rod bearing failure. It started in the m3post bearing wiki page with RG's original measurements by Van Dyne. Then it progressed to gather specs. It's not hard to calculate the tolerance stacking specs if you know how. From there, you can use your own knowledge of engines to decide if that would cause an engine to blow or not.

I asked Bert to break it down. Here's what he gave me:

This information came directly from the BE blueprints with BMW 088/089 bearing wall thickness substituted from the actual BE values.

Rod bore specs range: 2.2047 - 2.2052
Rod journal specs range: 2.0464 - 2.0468
Rod bearing thickness range: 0.0783 - 0.0786

To calculate the small end of the tolerance stack: 2.2047 - 2.0468 - (2 * 0.0786) = 0.0007 inch
To calculate the large end of the tolerance stack: 2.2052 - 2.0464 - (2 * 0.0783) = 0.0022 inch
Nominal clearance: 0.00145 inch*

* This is the theoretical nominal clearance. It matches the exact clearance calculated by averaging the measured clearances from four different S65 engines using 088/089 bearings.

Now, doing the same for 702/703 bearings:

Rod bore specs range: 2.2047 - 2.2052
Rod journal specs range: 2.0464 - 2.0468
Rod bearing thickness range: 0.0782 - 0.0784

To calculate the small end of the tolerance stack: 2.2047 - 2.0468 - (2 * 0.0784) = 0.0011 inch
To calculate the large end of the tolerance stack: 2.2052 - 2.0464 - (2 * 0.0782) = 0.0024 inch
Nominal clearance: 0.00175 inch**

** This is the theoretical nominal clearance. It matches the exact clearance calculated by measuring a full set of virgin 702/703 bearings on a full set of virgin connecting rods.

Let the reader judge whether or not 0.0007 or 0.0011 inch (for 702/703 bearings) clearance is a safe value for 8400 RPMs and 10W60 oil, and whether or not these clearances could lead to premature engine failure.

[Green-Eggs]

Originally Posted by ham_sammich

I'd like to see them measure 50 sample , stock engines and come to a conclusion. I believe that to be a significant enough sample size to draw conclusions from.

The original sample size was 10 engines as shown in the m3post wiki. Eight of the engines were measured by Dinan. Dinan also provided the anecdote that they've measured over 80 while building their strokers, and "they all measure about the same." I'm sure Bert would give his Dinan contact information if you really needed to call and confirm and if this was all it took to put this to rest.

I don't believe that every single engine was assembled exactly the same with identical clearances.

That's the exact definition of tolerance stacking.

Thus a universal solution cannot be found. I've seen bearing examples that showed debris trapped between the bearing and the connecting rod bore, creating a high spot and centralized wear in that spot. Explain that. How do you quantify that into a universal solution? You can't.

Larger clearances don't affect or fix assembly contamination. That's a basic assumption that I would have assumed we all agreed upon without the need to explain or discuss it.

3. In order to fix your specific engine permanently, you would have to assemble, measure, adjust clearances, measure again and repeat until the engine is assembled with spec clearances.

This is exactly how race shops build engines.

Originally Posted by tdott

infact they are also faulted with sending whichever bearing they feel like to some customers. You were even a victim of that. You wanted Calico coated oem clearance bearings but you were sent "revised thickness Clevite bearings". Why aren't you saying VAC is biased also? They even sent you something you didn't order, yet you are okay with it?

I didn't realize he was one of the guys who was victim of this. I remember the story. One guy was even told it was his fault because he didn't request the Clevite bearings when he ordered.

Originally Posted by doogee

I think what people are forgetting is VAC used to sell OEM coated bearings. This is not what they sell now.

See immediately above. Three people on this forum have reported ordering bearings thinking they would receive the new Clevite ones, but getting shipped the old bearings instead. In one case, they blamed the customer for not saying he wanted the newer bearings.

Originally Posted by IanMan

The VAC coated bearings are actually just as bad if not worse as the stock bearings. The coating further decreases the clearance between the bearings and the crankshaft.

This is not the case of the new VAC/Clevite bearings. They are OEM clearance, and use the same H-Series Tri-Metal Clevite bearing process as BE. Besides the target clearance, the coating is from Calico instead of Clevite. Most high-end race shops that we deal with quit using Calico a few years ago. Other than that, if you want OEM clearances, the VAC/Clevite bearing is a very nice bearing.

Originally Posted by IanMan

OEM bolts are prone to being torqued incorrectly due to the torquing process so that would explain a lot.

OEM bolts when torqued correctly are very good. In BE measurements, they consistently yielded the least bore distortion. I've seen the photos too, and I'll offer comments on them a little later.

Originally Posted by ham_sammich

The assumption is I'm defending VAC, I'm not. I'm defending free options and asking the all important question, what is actually causing the premature wear. BE doesn't know, VAC doesn't know, hell BMW ///M gmbh doesn't know. So how BE claim their bearings are superior? Seriously? They measured some bearings and an engine and drew up a theory, and used the forums fear of bearing failure and a sales tactic to make you buy their product. Their data doesn't prove anything. You believe it does because you want it too. FML.

Wow, that's full of misinformation and false assumptions. From my observations, the people who have read the articles, the m3post wiki, and followed the subject for the past few years all know it. Maybe that's why people think you are biased?

Originally Posted by ham_sammich

I understand. Don't assume the tolerances are too tight. No one has proven that yet. Just opinions and conjecture.

I guess 0.0007 inch clearance is sufficient even though the bearing manufacturer themselves say it isn't. Sigh.

[Green-Eggs]

Originally Posted by doogee

BE Bearings @ 5130 Miles. Coating significantly worn off for stated mileage. Upper left is especially bad. Keep in mind the areas that look worn in the center of the bearing appear to just be reflection of light. All the wear is closer to the parting lines.

Saying they are "significantly worn" is not remotely true. Due to the angle of the photo, that could be barely worn at all; and in fact looks like it's barely worn at all.

VAC Bearings @ 33,500 Miles. Supercharged. No visible wear. 6.5X the mileage that are on the bearings above.

I know you've been around long enough to know those bearings were using bolts with bore distortion. The bore distortion gives extra clearance at 90-degrees. I guess I'm wondering why this keeps being shown as if it has any meaning as a valid comparison -- when it doesn't.

For those wondering, here's what a set of these SAME bearings look like @ 1500 miles using OEM bolts with no bore distortion. This is an NA motor. If you want to see excessive wear for the mileage, and the coating significantly worn off, I think this more than fits the definition.

Click photos for enlarged images.

My argument isn't that BE Bearings are no good, I'm just proving that any evidence that is negative towards BE isn't acknowledged by anybody that is part of their cult. The bearing is just fine, but the coating is quite possibly junk.

See above. Both are PTFE coating. But as mentioned earlier, most race shops quit using Calico years ago due to quality control issues.

Originally Posted by anerbe

I'm curious on the wearing close to the parting lines.

It's not the same wear near parting lines as we see with factory bearings. Factory bearings are often heavily worn or damaged right at the parting line. These look like very mild wear about 3/8 inch above the parting lines.

Unless there are two different V10's with BE Bearings pulled and shown, as mentioned earlier, the shop thought these looked so good they reinstalled them. I believe they also mentioned this was the first time they've ever seen bearings good enough to reinstall. So odd that one or two people think these are trashed, but the ones I've shown above -- using OEM rod bolts and the absence of bore distortion -- are never acknowledged.

According to this reference, we should see more wear (if any) across the center of the bearing, uniform 2/3 axially, reducing as you get close to the parting line:

Uniform wear pattern over approximately 2/3 of the bearing’s surface. Wear
should diminish near the parting line ends of the bearing, and the wear pattern
should extend uniformly across the bearing in the axial direction.

https://www.mahle-aftermarket.com/me...s-brochure.pdf

The oil starvation pics looks like examples of failed bearings (as we see in failed bearing pictures on this site).

Out of round bore look to be similar to the examples for cylinder 10 and 5 of the S85 pic.

So...not the fault of the bearings. Good to know.

Originally Posted by serranot

So, the BE naysayers complain there is not enough data to support BE's conclusions, and then to support their conclusions, they cite to one set of BE bearings with wear and one set of VAC without.

And they always consistently manage to use the same example of rod bolts with bore distortion. I believe that flawed comparison has been pointed out every time it comes up. So what are the chances that it keeps coming up, and why does it keep coming up? I stopped believing in these coincidences a long time ago.

[Sneaky Pete]

Originally Posted by serranot

BE has a working theory supported by its data.

But thats the problem...the theory isn't supported at all by "real world" data.
For example: If the S65's RB clearance specification is insufficient how are engines rebuilt with factory RB clearance able to cover high mileage and have bearings in good condition upon disassembly?
If the S65's factory RB clearance specification is insufficient such that it causes engine failure then most S65 engines should have already failed, not just a small %.

In any search for a theory to explain a phenomenon, you look for the simplest and neatest theory that satisfies all the noted outcomes. Not one that requires numerous logical contortions, a complete disregard of common sense while at the same time failing satisfy any of the outcomes other than engine failures are often likely to have an insufficient RB clearance component.
BEs tight factory RB clearance theory is a classic example of confirmation bias with extra pretzel logic on the side.

Originally Posted by ksteckba

To be fair, any argument made that BMW could have easily changed the bearing specs from the S85 to the S65 is completely disregarding the legal implications of such a fundamental design change. If they did make a significant bearing design change for the S65 and a class action suit was filed for the S85 owners, then how do you think the outcome would be affected?

Yet BMW in fact did indeed make many fundamental changes to the S85 design when building the S65 platform. Not least, hardware changes to the ionic anti knock system, a complete vanos redesign, a new lubrication system and of course a new crank.
BMW had the ideal opportunity during the S65 design to make any bearing clearance changes that they deemed necessary. If they were at all concerned about the legal implications they would simply keep the same RBs as used in the S85 (which they did IIRC) and machine the S65s new crank to give whatever clearance they desired....balancing out the new lubrication system to ensure other parts, such as the main bearings, were not compromised by increasing oil flow through the RBs.
The change would be invisible as BMW do not release proprietary information such as the RB specifications for these engines to the public domain and the new (shortened) crank would have a new part number.

Its not inconceivable that the blueprinted hand built pre production S65 engines performed perfectly well during extensive endurance and climate testing. But during the process of automating the engine building aspect of manufacture and/or in the production of the rod bearings by clevite, tolerance control was compromised. Such that at one end of the scale, engines with the correct specified factory RB clearance would be able to cover high mileage without problem while at the other end of the scale, engines with out of tolerance RB clearance would fail at low mileage. The majority of engines being spread somewhere along the spectrum.

[pbonsalb]

BMW also made 3 or 4 different cranks for the S65 but never changed clearance specs, at least as far as anyone has found so far. I do subscribe to the theory that a little more clearance won’t hurt and will probably help, but you can see how yours look when you change them and if they are among the 5 in 100 that come out looking good, I’d say you could put stock right back in. Mine were not among the handful of great looking bearings at 60k, so I will probably go extra clearance next change.

[doogee]

Originally Posted by Green-Eggs

See above. According to VAC FB page at the time they announced the new bearings, they are extra clearance BEFORE the coating is added. Multiple people have called VAC and depending on who you talk to, some get this same answer even today. It's not extra clearance after the coating is added.

You don't seem to understand how these bearings work. VAC or BE. Period.

Do you not understand these coatings are sacrificial? They are not made to last. Read my post about the pictures of the BE Bearings. I said the coating is junk because it's wearing off at 5000 miles yes, but did you miss the point where I said there is nothing wrong with the bearing?

On the VAC side, you get OEM clearance, and once the coating has worn off, you have some extra clearance.

NO coating will last forever.



I give up.

BE Bearings are the greatest thing ever created. VAC bearings are shit and no one should buy them.

I'm pretty sure that's what everyone wants to hear so there you have it

Enjoy your cult. You all choose to read what you want, and leave out what you choose.


I was genuinely interested in pulling my bearings this weekend to share with everyone but I just don't care to try contributing to the community anymore. It is a waste of time, and I can now see why the people who are actually educated on the topic and are unbiased don't post on the forums anymore. It's a shame.