I dunno about york yet, but I'd like to
Ive never cleaned the /2 slingers. I have had several /2's, many had sat for years. (I got one last week with a '92 tag on it still, it runs great after a carb cleaning) The whole motor has to come apart to clean them, so my thought is that I would clean them if I had to rebuild the motor.
I've never had to rebuild one.
I think its just something that bmw guys fret over. if the motor needs rebuilt, rebuild it. but why take it apart if it doesnt need it?
Oh, and I'd suggest running non detergent oil in the engine, as the detergent type can break loose crud that is stuck somewhere, and that crud could hurt something.
But, remember, I'm no bmw expert (even tho, believe it or not, I did spent 200 hours getting BMW factory certified about 20 years ago)
But thats what I do to MY /2's