Proposal for Self Cleaning Slinger Rings

[capebretonmarkbmw]

Nice to see you are still on this, I have a thought on the oil ring below the wrist pin. This is done as Porshe has them for there cars. I wonder if a longer connecting rod and a racing type piston would give you the same affect and be lighter at the same time. Mark

[miller6997]

If the slinger is self-cleaning, then why have it at all? Where does the crap go if it doesn't get trapped in the slinger?

[Matteo]

I agree. If you don't want the crud to be trapped in the slinger just install a flat plate, no cup at the parameter. Viola! "Self cleaning".

[Grant R26]

I’ve really enjoyed reading the comments on slingers.

Years ago, Vech’s article gave me Slingerphobia…a fear of debris packed slingers. I still wake up in a cold sweat.

I guess the BMW engineers looked to the slingers as a debris reservoir like the sludge traps in Brit bikes, never dreaming these bikes would still be driven 50 years down the road. Arguably, they could have been better designed but they-are-what-they-are.

My questions: I use rare-earth magnetic plugs to catch the magnetic debris and change oil every 800-1000 miles. The quality of modern “vintage” oil is vastly superior to the sludge that no doubt sat in my bikes in the 50s and 60s.

So…considering the above, what might the working life of a new set of slingers be ? The steel/iron debris is picked up by the magnets and oil changes. Modern oils are less prone to gum up in the slingers. The alloy/aluminium wear-debris concentration will be very low due to my frequent oil changes.

So taking all this into consideration, can I assume that my slingers are good for 50,000 miles ? 80,000 miles ? Once done are they even an issue worth worrying about ?

There must be lots of you out there who have had their slingers done in recent times…then later on, had reason to strip down their engine for other repair reasons…then looked at the slingers.

Are these slingers still gumming up like they did in the old days or remaining clear ?

Grant MacNeill, Toronto
R51/3 R27

[miller6997]

This slinger thread recurs from time to time, and my response to your questions will be a repetition of what I have said several times before. Take it with as many grains of salt as you consider wise.

The first R69S I owned, a '67, served me well as my primary transportation for ten years and 103,000 miles. Oil was changed faithfully at thousand-mile intervals. I never serviced the slingers, and in fact the thought never occurred to me, and I recall no advice that slinger service was a maintenance item. In 1977, the second owner handed me a wad of money (I think it was 7 or 8 hundred dollars) and rode away with a big smile on his face, celebrating his purchase of a sweet-running bike.

The second R69S in my garage (and still there), was owned by my brother from '67 to '96, when it came to me with a little over 50,000 miles on the clock. By then, the /2s were coming to be seen as "keepers," even "investments," not just transportation, so at 57,000 I pulled the engine and took it in for some serious preventive reconditioning, including replacing the slingers. At that point, the shop that did the work said that the slingers were about half full, and the crank and other critical moving bits were fine. It now has 80,000 miles on it and slinger worries do not disturb my sleep.

These are just two isolated, unrepresentative data points, but nevertheless, I can say that "gumming up in the old days" just doesn't fit my experience. One bike made it past the 100K mark with no complaints during my ownership, and the other went 57K and did not seem to be near destruction.

And no, I don't usually whistle in graveyards.

[CentexBeamer]

New member and new to R60/2's. I recently got the urge to purchase a 1967 R60/2 US model. The first thing I did was to verify that it was road worthy and mechanically sound. After Carb rebuilds and new tires and oil change, I took it out for a spin. Everything worked well except for a knock at idle coming from deep within. After reading about slingers and all the posts on this thread, I was hesitant to do it, but since I had no real maintenance history, I felt like i needed to do it so i got the manuals and proceeded to dismantle. when I finally got down to the slingers, i was both shocked and happy. Shocked that they were completely caked up all the way to the rim, and happy that I made the decision to get into the engine and check them. Also found source of the knock - noticable play in rod bearings which I will attibute to poor lubrication by stopped up slingers. I have included two pictures. Hope they download properly.

[miller6997]

Do you know the mileage on the engine?

[CentexBeamer]

48000 on odo when I bought it but it was broke so no tellin. I don't think there is an extreme amount because the bike doesn't have obvious wear signs. Forgot to mention: one wrist pin bush was about 1/8 of the way out and rear main bearing was beginning to spin on crank

[urbanistica]

The thread that will not die... there's nothing much wrong with my R69 engine, but I get cold chills thinking about its 76000 miles and what those slingers might be doing. The thing that drives me out of my mind is that I might send the engine out for service, and be told that the slingers are clean as a whistle... and unless I'm replacing the main bearing anyway, I'm out about the same amount of cash as I would be if the slingers did need cleaning...

But what interests me is: if the slingers are effective at capturing fine particulate in the crankcase, why not add an internal slinger, not on the crankshaft, but elsewhere - maybe in its own small add-on reservoir - that can be accessed easily, coming out of the oil pump somewhere? I very high RPM slinger that oil ran through, with a slightly smaller capacity in the annular area would a) tend to catch particulate before it got further, and b.) fill up before the main ones did. By looking at the extra slinger, you'd know roughly what the state of the other two was, and you'd likely extend the service period significantly.

[morrison830]

New BMW R50/2 owner here, so please indulge my ignorance on this machine, as well as posting on this forum. I have recently acquired a '65 R50/2 that has been in storage for the last 35 years. So far, it has cleaned up very well, generally good on the mechanical side, is operative and I am in the process of getting the title issues resolved. The odometer shows 30K miles...the previous owner was a BMW dealer in the Austin, TX area (took it in as a trade-in)....very little known about the previous owner or maintenance history. SO, after doing research on this "animal", I am still perplexed as to how/why BMW came up with the "slinger" idea (seems to me to be very "Un-German"). At any rate, I've read enough on the forum to now be concerned about this component. I'm somewhat tempted to dive into this project myself, yet, being a total novice to BMW motorcycle oddities, I'm leaning more toward farming this one out. I've become acquainted with Vetch/Richard at Benchworks...ordered several parts and had lengthy conversations with both of them (been very helpful)....I know they are more than capable to do the "slinger service". I could remove the engine myself and deliver same in that condition to a capable shop....would there be anyone closer to Kerrville/San Antonio/Austin who could do a good job for me??? Suggestions/opinions would be appreciated. Thx....Marc