so what exactly is a slinger

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so what exactly is a slinger

Post by schrader7032 »

There's a couple of articles on the slingers. Vech has one:

And Darryl Richman has one:

The problem does arise from high mileage (typically around 30K or beyond) but it also has to do with how the bike was ridden, the type of oil used, adn the frequency of oil changes.

In order to clean, even check, the slingers, the crankshaft has to be removed from the bike. With little knowledge and tools, this is not a job for the shade tree mechanic. Once inside, there's experience needed to inspect the bottom end (bearings, journals, etc.) and to decide what to replace.

This is a mechanic feature of the bike that you need to be absolutely sure has been taken care of. If the slingers become full, they can start the bottom end critical parts of oil and run a crankshaft, resulting in a big bill to repair.

It's not a big deal and there are several mechanics who can this job well. It's something that each of us have had to face. But once done, the bike should be good for another 30-40K miles. That's a long time in my book!!

Kurt in S.A.
Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

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My favorite slinger

Post by tkb »

Below, Joel Rapose's handsome hand holds a slinger (back side/crank view) freshly removed from my 1966 R69S with 35,000 miles. The machine was recovered from a shipping container in the weeds south of Sacramento, California. The bike looked unharmed, but its history was unknown. That, and the mileage left no escape from a check of the slingers.

Looking into the opening at the bottom of the slinger you can see that the slinger ring is filled with crud up to the edge of the hole, justifying the wisdom of the engine teardown. Fortunately, the crank was undamaged.

Slinger cleaning is a sure means of getting to know the internals of your machine on close personal terms. It is also a project that can suck you into a complete restoration. Well, with a Barrington manual in hand, why not?

Tandy Bozeman


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so what exactly is a slinger

Post by luluparr »

thanks to all who replied; i appreciate the advice and suggestions !

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so what exactly is a slinger

Post by VBMWMO »

i am looking to buy an r27 or/2 and have been seeing ads that mention the slingers have been done/replaced/cleaned.
i assume it has something to do with oiling the internals (crank maybe) but don't know. can someone recommend an article that explains how they work and why, under what conditions they should be cleaned/replaced? ie is it just high mileage or is it old age or combo or ???
finally, since i am looking for a nice driver is it something that will want to already have been done or can the bike be safely ridden without destroying something or making it more expensive later to fix? what does it take to clean/replace them? is it an issue on both bikes or just one singles or twins ? any help would be appreciated !

Dedicated to the Preservation of Classic and Antique BMW Motorcycles.

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