RL, very interesting.

Can you tell us more about the 2 photos. Hope did you happen to obtain Pistons broken in with the 2 methods? Was the mileage on each roughly the same? What gasoline was used? Other than the break in period, were the riding styles similar? Was RXP used in either or both bikes?

The variances in the photos was striking. It's hard for me to believe that the only difference was break in method. I imagine that brand and grade of gasoline along with the use of RXP could make a huge difference.




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I took the photo from the Motoman Break-In site. Here is what the text is:

A Picture's Worth A Thousand Words:

The piston on the right was broken in as
per MotoMan's instructions.

After a full season of hard racing:

- Perfect Ring Seal ...
- No Scuffing ...
- Lots of Trophies !!!

These Honda F3 pistons show
the difference.

Although these pistons came out of engines which were raced for a full season, they weren't set-up with any special clearances or other preparation.

These engines were never worked on prior to being raced. They were totally stock as built by Honda.

The only difference was the break in method they used...

The one on the right was broken in as per MotoMan's instructions.

The one on the left was broken in exactly according to the owner's manual. The resulting leaky rings have allowed pressure to "blow by" down into the crankcase on acceleration, and oil to "suck-up" into the combustion chamber on deceleration.

Needless to say, this bike was slow !!

It's up to you:
The loss in power from an easy break-in and the resulting poor ring seal can be
anywhere from 2% - 10% !!

In other words:
The gain in power from using this break-in method can be anywhere from 2% - 10% !!

 

It isn't my point that any specific break-in method led to each of the different K1600 engine failures. My point is that the K1600 engine failures, and so many other auto engine failures, further convinces me that ring seating and keeping the combustion area clean is important.

We each choose our own manner of new engine break-in.

Turning the cards dealt over to see if the luck of the draw gives us an engine prone to failure just isn't good enough for my.

Best practices, plus a good extended warranty, is my belt & suspenders way to manage the risk.

 

Call me a skeptic, but I have a very hard time believing the only difference in those two Piston pictures is the break-in procedure.

One sample of each?
Any engineer knows it's dangerous to draw conclusions like that from such a small sample size.
To many unknown factors IMHO....


btw- at 160HP I could give a rip about 2-10 power gain.....I don't race my K1600. Engine longevity is the main concern.

 

Engine longevity is the main concern.

Mine too.

I find comfort in a very specific procedure for engine break-in.

Thinking more about it though, if longevity and the full designed power aren't mutually exclusive, then why not have both?

 

http://www.eci.aero/pdf/breakininstructions.pdf

Page 16.

A new or overhauled engine is an expensive investment. Break‐in is the most important time in the life of your engine and is critical in determining its performance capability. Seventy‐five (75%) percent of the total normal wear of an engine occurs during the break‐in period. According to Federal‐Mogul (the leading authority for engine bearings throughout aviation's development era) new piston rings, pistons, and refinished cylinder bores will be more sensitive to break‐in than any bearings. Any break‐in procedure acceptable for rings and bores will be agreeable to the bearings. Therefore, the first consideration in the break‐in mode should be to accomplish the ring to bore seating.

 

Detailed instructions like this:

http://www.motorcycleextremist.com/Motorcycle-Engine-Break-in-the-Right-Way!.html


Method A:
By the Book -
Follow the manufacturer's recommendations found in your bike's owner's manual.

Method B:
The "Other" Method (more aggressive) -
Break-in the engine using a wider range of varying engine speeds, including intervals of short duration high RPM runs.


Method "A" Example:
The following is an excerpt taken from page 50 of the Triumph Daytona 675 owner's manual, which stands out among others I've reviewed as being one of the more reasonable and functionally beneficial manufacturer recommendations I've come across,

"Breaking-In:

Breaking-In is the name given to the process that occurs during the first hours of a new vehicle's operation. In particular, internal friction in the engine will be higher when components are new. Later on, when continued operation of the engine has ensured that the components have 'bedded in', this internal friction will be greatly reduced. A period of careful breaking-in will ensure lower exhaust emissions, and will optimize performance, fuel economy and longevity of the engine and other motorcycle components. During the first 500 miles (800kilometers):

• Do not use full throttle.

• Avoid high engine speeds at all times.

• Avoid riding at one constant engine speed, whether fast or slow, for a long period of time.

• Avoid aggressive starts, stops, and rapid accelerations, except in an emergency.

• Do not ride at speeds greater than 3/4 of maximum engine speed. From 500 to 1000 miles (800 to 1500 kilometers):

• Engine speed can gradually be increased to the rev limit for short periods. Both during and after breaking in has been completed:

• Do not over-rev the engine when cold.

• Do not lug engine. Always downshift before the engine begins to 'struggle'.

• Do not ride with engine speeds unnecessarily high. Shifting up a gear helps reduce fuel consumption, reduces noise and helps to protect the environment."


Method "B" Example:
Break-in the engine using a wider range of varying engine speeds, including intervals of short duration high RPM runs.

I think the two best places to do this break-in is either the canyons or the race track. If you live near some canyons, go straight there for your break-in. If you can haul your bike to a race track, that's a great option as well. Do not "lug" the engine around at low RPM at all, and don't cruise around at the same RPM for any real length of time, but rather you should be fluctuating the RPM consistently. Don't even bother riding on the freeway at all for your first 500 miles, unless it's basically just on and right back off. One of the worse things you can do is baby the engine too much during break-in, along with running too hard too fast. You have to find a kind of happy medium between the two.

Oil and Oil Filter Change Schedule Summary -
Make sure no synthetic oil is used during the first 1500 miles. Use only regular motorcycle specific SAE 10W – 40 mineral (petroleum) oil that meets or exceeds the API SG and JASO MA2 standards. If you're not sure what oil is in your new bike, change it immediately to this oil, and change the filter as well. While 10w - 40 is best for most, if your particular climate or engine requires something different, then by all means use it.

50 Miles - Change oil and oil filter (Mineral Oil)
200 Miles - Change oil and oil filter (Mineral Oil)
500 Miles - Change oil and oil filter (Mineral Oil)
1500 Miles - Change oil and oil filter (Mineral Oil or Synthetic Oil as Desired)


The following is my own interpretation and idea of what I consider to be a good example and set of guidelines for using Method B.

Method B: Using the 2009 Triumph Daytona 675 as an Example

If you're breaking in a different bike than the Triumph Daytona 675 used in this example, simply use the initial RPM calculations for the max RPM of your bike, and raise them by the same amounts as our example here.

1.) Before Riding -
Ensure that the break-in oil of your choice is in your engine, and double check to make sure that the oil level is correct. Start the engine and allow it to reach proper operating temperature before actually riding the bike. Once the engine is properly warmed up, it's time to take it out for your first break-in ride.

2.) Your First Ride -
Make sure you can get the bike out on the road with the lightest traffic possible, and some place where you can open the bike up a bit, at least in the lower gears. Be sure to ride the bike and vary the engine speed from the low-midrange to upper-midrange area your power band while driving for a round-trip total of 20 miles.

During the first 10 miles you should be fluctuating between the upper-low to the middle-midrange area of your power band. Basically you'll want to stay in the 1/3 to 1/2 area of your max RPM range. For the 2009 - 2010 Triumph Daytona 675, that has a "real" max RPM of 13,900, which is an indicated 15,000 on the tachometer, this range is from about 4500 to 7500 RPM. Be sure to fluctuate the RPM between these ranges, and use engine breaking as much as reasonably possible.

After you've completed your first 10 miles, park the bike and turn off the engine. Let the bike sit for 20 minutes, and then start it back up. Make sure that the engine as at normal operating temperature, and then proceed on with the last 10 miles of this 20 mile ride in the manor described in the following paragraph. Please note that the reason for this brief cool down is not for the purpose of what would be referred to as "heat cycling", but rather it is an attempt to allow the friction points inside the engine, where there may be a few how spots, to even out their temperatures with the surrounding metal.

During the last 10 miles of this 20 mile ride you'll be fluctuating the engine speed as before, but this time raise the top RPM by 1000 to 8,500 RPM. So, you should be keeping the engine between 4500 and 8500 RPM. Remember to use engine breaking as much as reasonably possible during this ride.

3.) Your First Oil and Oil Filter Change -
At 20 miles, change the oil and oil filter while the engine is still warm. Inspect the used oil and oil filter for any metal debris. Some metal flakes and or shavings are often found in the used oil and oil filter during this initial break-in stage. Don't be alarmed if there are some, as this is perfectly normal and acceptable.

4.) Your Second Ride -
Before starting the engine, first check the oil level and make sure it's where it should be. Now it's time for your second break-in run. After warming the engine up to the proper operating temperature, take the bike out for a 30 mile roundtrip ride. You'll be fluctuating the engine speed regularly as before.

During the first 15 miles of this 30 mile ride you'll be varying the engine speed from the mid-midrange to the upper-midrange. So were adding 1000 RPM to our bottom and top RPM range, which brings us to the 5,500 to 9,500 range.

After you've completed your first 15 miles, park the bike, turn off the engine, and let the bike sit for 20 minutes. Now start it back up, and make sure that the engine is at normal operating temperature before riding on. Proceed on with the last 15 miles of this 30 mile ride in the manor described in the following paragraph.

During the last 15 miles of your 30 mile ride, you'll be fluctuating the engine speed as before. However, this time raise the top RPM by 1000 to 10,500 RPM. So, you should be keeping the engine between 5500 and 10,500 RPM. Remember to use engine breaking as much as reasonably possible during this ride.

5.) Your Second Oil and Oil Filter Change -
At 50 miles, change the oil and oil filter while the engine is still warm. Inspect the used oil and oil filter for any metal debris. Some metal flakes and or shavings are often found in the used oil and oil filter during this second stage of the break-in period. Don't be alarmed if there are some, as this is perfectly normal and acceptable.

6.) Riding out the Rest of your Break-in Miles -
The remaining break-in miles should continue to be put on with varying engine speeds applied, including brief trips up near redline on occasion.

7.) Your Third Oil and Oil Filter Change -
At 200 miles, change the oil and oil filter while the engine is still warm. Inspect the used oil and oil filter for any metal debris. Some metal flakes may be found in the used oil and oil filter during this third stage of the break-in period. Don't be alarmed if there are some, as this is perfectly normal and acceptable.

8.) Continue varying the engine speeds while riding the bike as before.

9.) Your Forth Oil and Oil Filter Change -
At 500 miles, change the oil and oil filter while the engine is still warm. Inspect the oil and oil filter for any metal debris. Again, some metal flakes may be found in the oil and oil filter during this forth stage of the break-in period, so don't be alarmed if there are some, as this is perfectly normal.

10.) Continue to vary the engine speeds while you ride as before. At this point you can incorporate some short stints on the freeway if you want to, but keep mixing it up with plenty of street riding.

11.) Your Fifth Oil and Oil Filter Change -
At 1,500 miles, change the oil and oil filter while the engine is still warm. Now would be a good time to switch to a full synthetic motorcycle oil if you so desire. Otherwise, just make sure that you use a good quality motorcycle oil; appropriate for your particular engine and circumstances. As always; inspect the used oil and oil filter for any metal debris that may appear. Metal flakes are sometimes found in the used oil and oil filter during this portion of the break-in period. Don't be alarmed if there are some, as this is perfectly normal and acceptable.

12.) For all intents and purposes, your new engine should be considered as fully broken-in at this point, and you may ride the bike as you wish from this time forward. Always be sure to perform the required and appropriate routine maintenance required for your bike.


Conclusion:
So that's about all there is to it. I hope this article has helped you to understand the break-in process better, and will serve as a good general guideline to use when it's time for you to break-in your new engine.

 

Detailed instructions like this:

http://www.motorcycleextremist.com/Motorcycle-Engine-Break-in-the-Right-Way!.html
........................

Oil and Oil Filter Change Schedule Summary -
Make sure no synthetic oil is used during the first 1500 miles. Use only regular motorcycle specific SAE 10W – 40 mineral (petroleum) oil that meets or exceeds the API SG and JASO MA2 standards. If you're not sure what oil is in your new bike, change it immediately to this oil, and change the filter as well. While 10w - 40 is best for most, if ............
.........

API has listed SG as obsolete for some years now. The newest are SM & SN. Some good advice here though.

 

KTM & BMW run-in their engines before exiting the factory for delivery. Maybe most other manufacturers do the same.

(KTM does this run-in with mineral oil, then changes to synthetic.)

This run-in is a final check, done at high RPM, to make sure there isn't something which will quickly fail.

In no way does this seat the piston rings.

 

Could you describe what happens in the piston ring seating process? My impression is that in the old days of cast iron bore engines with rough lapped finishes, the harsh break in procedure used the new sharp corners of the rings to shave down the rough surface of the cylinder bores to a smooth geometric shape that matched the exact shape of the rings. This provided a tight ring seal that produced more power and minimal oil consumptions.

The new aluminum engines have a Nikasil plated or lined cylinder bore. The Nikasil is already very finely finished and is so hard that there is no way a steel ring is going to shave or alter it in any way. If this is the case, I don't understand where any ring seating is going to happen, no matter how you break in the engine. Where is the error in my thinking on this subject?

 

Issue of light weight?

In the years I've been riding BMWs there have been many issues discussed. Heck, the R1100 pinged terribly. Yet I don't recall any discussion of piston or ring failure. (RXP cured my R1100GS of pinging completely.)

Maybe the search for the lightest possible K1600 straight six yielded pistons that aren't as durable as really needed for ethanol contaminated gas? Gas that burns dirty.


Issue of quality control?

While I suspect that BMW K1600 engine components are sourced outside Germany, I have no evidence of where they come from. What I wonder though is whether there has been a reduction in quality control, or insufficient component testing, yielding additional engine failures.


Is there a similar experience over on AdvRider with the new R1200 engine? Varnish and coke build-up leading to failure? A search yielded no results. So, maybe I missed the right search term, or this is an issue with the K1600 engine.

What about the K1200 & K1300?

 

It is obvious from the photos and videos that the K1600 engine is assembled in Germany.

It is also apparent that the piston has sufficient depth to be considered durable.

So, why has there been a noticeable number of failures? Especially compared to the complete lack of failures with the new R1200 LC, which sells in far greater numbers?

 

A smaller combustion area should burn more efficiently than a large one. The K1600 has relatively small 267cc areas, compared to the bigger 600cc R1200 engines. Both are four valve engines.

On a side note: It has been decided that the perfect cylinder size is 500cc. So, you will now see more, and more, 2,000 cc 4 cylinder, 3,000 cc 6 cylinder and 4,000 cc V8 engines in autos.

 

Look about 30 seconds into this video... new K16 at high revs at the factory!
Wie entsteht ein Motorrad? - Deutschlands modernste Motorradfertigung

 

Any way to view that video without downloading the app (or worse)?


Sent from Motorcycle.com Free App

 

Video can be seen from a computer with no app installed.

 

Nikasil has been around for a long time. I suspect that it is the rings which are shaped to fit the cylinder. The nature of the rings is that they fill the gap between the piston and cylinder wall, keeping the combustion confined. To do this the rings must be free to move within the land, or groove in the side of the piston. When the dirty combustion gasses, or oil from below, get past the rings, we end up with varnish and worse yet coke (burnt oil deposits).

Thin rings, sliding up and down the long piston travel, will shape to the irregularities in each cylinder.

The better, and quicker, the rings take on the proper shape, the better/cleaner the combustion will be.

Despite the seated rings, ethanol contaminated gasoline burns leaving more deposits in engines designed for pure gasoline. Deposits which will lead to carbon deposits which will allow for pre-ignition.

 

So you say that the detergents in gasoline take care of carbon build up?

Honda TRX 450

At least with fuel injection it is hard to run an engine this rich.

 

I'll say this.....There isn't a single auto or motorcycle manufacturer that suggests beating the **** out of your machine as a way of breaking it in. With that said, I've done a factory tour of the Harley plant in York, and every new bike that comes off the line is immediately run up to 100mph on a dyno before getting crated and leaving the factory. I'd assume that most bike manufacturers do something similar.

But.....

A new vehicle isn't just breaking in the engine. It's also breaking in the tires, the final drive, the clutch, the brakes, and the transmission. To me, it sure seems foolish to beat the snot out of something new in direct contradiction to what the company that makes and covers the vehicle states.

As always, do whatever you think is best, but I've never had an engine failure breaking in something the way the manufacturer suggests.

 

:gm

With over 25 new vehicle purchases and 15 of those being new motorcycles I've always followed the OEM recommendations for breaking in a new engine.
Never a single issue with the engine and none of them has ever used any oil between changes, including the K1600.

I've seen several EOL vehicle runs on a dyno and yes they do run them up to around 90 - 100MPH to check the operation of the engine, transmission, and other components.
But, they do so in a very controlled fashion and get nowhere near the red-line.

Continues to amaze me how many backyard mechanics know more than the companies that built the machine.
But, do as you wish.......your cash and your machine.

I'll continue with what is suggested in the OEM owners manual and what has worked for me over the last 35 years.


btw -
To tie the couple of recent piston failures to a break-in procedure is a huge stretch IMHO......nothing but pure speculation and a lot of conjecture.
Completely ridiculous IMHO.
Nobody here has any clue as to what caused those issues and it's foolish to suggest otherwise.

 

I have always used my version of the Motomans run in procedure of every new bike that I have had, no exceptions. All I can say is a lot of motorcycles. None have had an oil usage issue, none have had the slightest engine or any other mechanical issue for that matter all have been on the upper area of both power and fuel mileage range. With out exception, all my first oil changes at between 50 and 200 miles have been with full Synthetic as soon as it was available, mostly Mobil 1. This was true with my first Beemer a '72 R75/5 toaster tank. and roughly true with my earlier bikes.

I think a lot of what some have seen with their K1600's are a result of a very timid break in procedure, a lot of lugging and near lugging because the engine has such hi low RPM torque. Coming from a hi torque low RPM V Twin to the K1600 would lead one to ride the Beemer the same way.

My #2 in the US '12 K1600GT bounced off the rev limiter hundreds of time playing in the twisties. On more than a few occasions it made the 211 mile trip from Caliente, Nv to Tonopah, Nv cruising in excess of 120 on the GPS. The bike more than once cruised a particular stretch never below 145 on the GPS, loved the howl of the Remus pipes. From what I have heard from the current owner, the bike still runs perfectly with no problems.

This is to echo and agree with RL's initial post in this thread.

 

Or, even better yet, if the thread doesn't interest you, don't click.

I refuse to stop asking questions, to stop exploring better ways, or to stop seeking the experience of others.

It is amazing how forums end up with distinct groups:

The majority who lurk and learn.

Those who offer original content.

Those who complain, taking every conversation negative.

 

We learned some time ago that BMW takes forums seriously, this one too. They have reacted to threads here. Making our experiences known and our reactions to the experiences, has brought about positive reactions from BMW.

Comparing the K1600 to the new R1200LC begs the questioning about why this is a K1600 issue.

I've offered a number of reasons why it might be happening.

No clue?

Well, I think we have a number of clues, because of the photos. We also have the experience of others, from other sites, regarding what leads to damage.

What is the chicken, or the egg, in this serious issue, remains unresolved. If BMW finds the answer, it will be kept secret from us. That is unless a dealer finds out and tells one of those afflicted with the failure.

In the mean time, I remain resolved to follow a precise break-in procedure and to purchase 7 year extended warranty. Belt & suspenders.

As I learned, when selling a motorcycle within the term of an extended warranty insurance period, the insurer must prorate the policy cost and refund the unused portion.

 

Possible engine failure causes (just theorizing):

- Ultra compactness of cylinder block with closely spaced pistons and many very thin cross sections. Could lead to a lot of distortion caused by poor heat conduction (hot spots) and high mechanical stresses.
- Too much power being produced out of a small, light weight engine.
- Some sort of resonant vibration being produced through the drive train.
- I have heard mention of piston skirt slap against the cylinder walls.
- Combustion chamber design problem leading to excessive accumulation of carbon deposits.
- Engine mounting points causing engine block stress and distortion.
- People running the engine on low octane fuel.
- Internal engine lubrication problems.

The reports of engine problems with the K1600 seem to be far higher than the R1200 2 cylinder engine. Of course, the K has 3 times as many pistons, so that could be part of it. The only reports that come to mind for the WC 1200 engines are the main center clutch fastening nut coming loose with catastrophic results.

 

Maybe that's it, BMW & Ricardo pushed the envelope too far.

However, there have been so many without issue.

Maybe the K1600 engine requires a higher metal inspection/testing standard.

Regardless, the K1600 is a great motorcycle. One I had no concern about riding across the continent, as speeds approaching Cannonball.

It just seems to me that a back-up plan of insurance is prudent because of the expense of repairing the K1600, should the Luck of the Draw not favor you. 3 years or 36k miles comes very fast if you ride a lot.

 

Why not ask all the owners who have experienced piston failures to let us know how they broke in their engine.

Or, find 10 guys who broke theirs in the factory recommended way and 10 who used "motoman's" way and tear down the engines and inspect the pistons.

 

Why not ask all the owners who have experienced piston failures to let us know how they broke in their engine.

Excellent idea.

RL, would you start a poll? Let's get some answers just from those who have actually experienced the issue ...

What I would like to know is:

How many actual (or potential, like ... just discovered oil in the condensate tube) failures have occurred among owners who follow this forum?

IF you were responsible for the break in procedure, which did you use?
A) by manual B) Motoman C) other

What brand, type (synth or dino), and viscosity of oil do you use?

Do you use ethanol (we all get caught out and have to on occasion) frequently?

What about octane rating? A) don't care B) by the manual (89), or C) highest I can find

Claims of hysteria aside, I think this would be very useful data

 

Several people have reported that they broke in their engines per the manual and that the engines run great and use no oil. That proves that it is not necessary to use the moto man method to obtain those results. Would the moto man method produce even better results? Maybe. Who knows. How would a person go about measuring that improvement in performance?

Doing a survey of break in method used for those who have piston/ring related engine failure would require a fairly large number of that type of engine failure to get reported to be meaningful. Plus you have to know the ratio of break in method in the general population before you can correlate the survey results to any meaningful conclusion. I don't think it is doable.

 

Doing a survey of break in method used for those who have piston/ring related engine failure would require a fairly large number of that type of engine failure to get reported to be meaningful. Plus you have to know the ratio of break in method in the general population.

So if only say, 8 people are affected, but all 8 of them were breaking it in by Motoman method, and running the highest available e-free octane available ... that wouldn't be meaningful information?

Somehow I think that if that were the case, you'd be jumping all on it

 

Re-Post from White Smoke debate

I still wonder whether this all relates to an inherent design issue.

The pistons may well be frail around the ringlands, the mixture may be too lean when using low grade fuel (pinking) & the ECU may not respond promptly when power is called for, after a long period on an even throttle.

However I really do wonder about the cylinder spacing, some 5mm apart if I understand correctly, to keep the engine so narrow, which must mean there is no coolant flowing between each cylinder. Many of the failures seem to have arisen after a lengthy run, say on the freeway at speed. Then the rider slows down for gas/whatever - the sudden heat build up must be enormous. Maybe the engine is turned off, so all that heat has nowhere to go. Are we witnessing a mild piston seizure scenario, which then cracks the ringlands as the engine is restarted. Are the cylinder bores distorting. In my experience, excessive pinking has usually lead to the piston crown collapsing, rather than ringland fractures (thankfully not for many years).

The BMW fix just seems to be to richen up the fueling & retard the ignition a tad. This will reduce pinking & mpg, but not address the inherent problem to my mind. This is where I like the idea of the Horex narrow angle V6 design, which is akin to the VW VR6 idea (& Lancia in the 1930s) only better. Horex achieve excellent packaging without spacing the cylinders so tight. More expensive to build, but hey, the K16 is the UberTourer after all. The warranty work & reputational damage must be costing BMW dear, but I doubt they will want to acknowledge any fundamental design issues are at play, particularly with the 'Bagger' 101 in the wings.

Still I am just a long term rider, not a tech wizzard. We must have some Technician/Engineers on here who can comment from the design perspective.

Ride Safe ............ KEN

 

I'd bet it's a combination of issues. It's a powerful, high-compression engine with narrow bore spacing and (inexplicably) no knock sensor. Run bad gas, clog an injector, or somehow get those cylinders hot and you're asking for trouble. If you run top-tier fuel, you won't have an issue with buildup in the injectors, on the valves, or on the pistons, but how many people do that religiously? I certainly don't.

While I think it's foolish to manufacture an engine like ours without a knock sensor, I'd wager that The Mothership did some manner of testing prior to unleashing it on the public. I doubt that the failures have anything to do with how the bikes were ridden or maintained, and I don't think it's fair to chalk them up to a design deficiency. It's just dumb luck, or perhaps a defect in those specific bikes.

 

If an owner is concerned about the matter, I would suggest calling around for a Zurich quote. I found a smoking hot internet price for my new bike, tire/wheel replacement coverage too.

Having the comfort that your downside risk is covered is a good thing for those who don't want the risk of an unexpected engine rebuild expense.

BMW made a statement with the Ricardo designed straight 6. A link to their well respected straight 6s in the autos. This statement appears to offer an unexpected challenge. Good thing it afflicts a very small number of owners. So very sad for those few though, as the time and expense to deal with it is significant.

 

My only argument with heat is that if it had these instantaneous heat blooms you should see the piston swell up and gouge the cylinder wall or the cylinder wall swell enough to pinch the piston. But, I have only seen two motors and neither had metal transfer to or from the pistons.

They honestly just looked like there was to much combustion (compression) and the metal in the ring land area was too soft so it just broke away. You could see with a magnifying glass where the cracks had "wiggled" back and forth allowing oil on different occasions (colors) to seep into the piston metals. Even after the chunks of piston totally broke off the piston they still remained right in place between the rings.

For 5 years I was a mechanical claims adjuster, not an engineer until later on but this really, really looked like weak metal in the pistons that just eventually gave way under hard compression (combustion). The 4-5 pistons I personally looked at had no metal transfer, no carbon build up until fresh oil began burning.

This is ALL my personal opinion and yours may vary but I did sleep in a Holiday Inn last night.