BMW Motorcycle engines made before 1970 have a unique, centrifugal oil cleaning system. There is no replaceable filter to trap dirt and debris. Instead, a pair of sheet metal rings called “Slingers” are used to do this job. They attach to the front and rear of the crankshaft assembly, and use the rotation of the engine to trap particles that are heavier than oil, and keep them from circulating around the engine. This process, along with frequent oil changes, can keep these motors operating for around 30,000 miles without any major services.
BMW specifies that these “Slingers” must be cleaned at certain intervals to extend the life of the motor. At some point, often around 30,000 miles, these traps become full. As this happens, they begin to dump grit and debris directly into the large connecting rod bearings that are part of the crankshaft assembly. This drastically accelerates wear. Unfortunately, not many owners of these machines paid attention to this service requirement. Most, if not all of these machines in service now would benefit from this service.
The good news is that we at Vintage Sales and Restorations can perform this service for you – at a fair and affordable price, in only a few hours. This service requires some specialized tools and knowledge that we gladly offer. Our basic “Slinger” service covers the following:
- Disassembly of the engine block.
- Inspection of engine parts.
- Replacement of all bearings, seals and gaskets.
- Cleaning or Replacement of Slingers.
- Cleaning and re-assembly of engine block.
As with any of our services, if there are other problems found, you will be asked to approve any additional work required.
You can choose to ship either your engine block alone, or your complete motorcycle to me for this service. Pricing is based on parts and labor required. You may also choose to have the engine block surface restored to new appearance, or simply cleaned.
**See our related services**