Windsailor, excellent points. Getrag knew darn well that gear lube was going to mingle with the yak grease in their "clean" bearings. They designed the gearbox to work in unison with a specific fluid. Not too slippery, with a certain body. At a BMOA lecture it was that BMW felt riders would not change the fluid often enough to clear the high quantity of particles shed by their gear boxes so they gave us "clean bearings". Originally the covers were billed as " new design with micro-filtration" Figure that one out. If you look at bearing failures on the 1150, miscibility with certain syns is still somewhat of a concern. Unproven fluid may help the gears only if the bearings survive. Redline is quality stuff and decently priced. Not top of line but very good. But is it right for the M94, M97 or 11xx six speed? I tried their Shockproof HD- couldn't get shed of it quick enough. Shifting was horrible. Amsoil was o.k., CRC Syn-Go OEM was silky smooth but its hard to justify at $45/qt and long term bearing compatibility is still unknown. Most 11xx riders want best value not over-shooting point of diminishing return. Getting back to what you said about the old Getrag interview, conventional multi-grades, just how much have they changed? If 75w90 conventional was not recommended for M97 at the time then how comfortable can one be with it today, or even with 80w90? Yes, it does seem that there ought to be a modern fluid that serves the "ideal" above but which one is that? How much is reasonable to pay for himmlischen Flüssigkeit? The new fluids are an essential component of modern lighter drive lines. But the benefits do not automatically extend to older equipment. For classic vehicle owners obsolete fluids have long been a problem . Most of us prefer Riding over training for lubrication engineer. But hopefully this discussion will rescue few M97's from an untimely death (including op's). A word on gear oil lab analysis: Visual is better. I've sent out samples with visible metal flake yet they came back "clean". If we could get reliable analysis then we could test the effectiveness of the the syns. Another way to shorten the list is to look at the base stocks and additive package for Mo 1 75w90, a known endgültige Lösung für Motorrad-Getriebe Frage.