Replacing BMW R1100 R rear main seals: Oilhead Boxer engine (like R1150)

Replacing the two-part rear main seals or crank seals (crankshaft seals) on my 2000 BMW R1100R oilhead engine. Same sort of process for R1150 engines even with the single seal. Not a difficult job, just be careful/methodical and don’t force things. It is also a great opportunity to take a few other bist apart and have a good clean up while you are in there. The clutch on this bike had recently been replaced (thankfully no contamination from this seal issue) but I would probably have changed it if it was s