I reviewed your K1100 website, Hans. It is concisely informative and well-assembled. Your comparison photos of gearbox lubricant should be seen by every new purchaser of a Brick so they understand the damage they could cause by not renewing the fluids before they head out on the highway looking for adventure. That old lubricant is a foul-looking brew!
Regarding E10 and your website discussion of it:
I am unwilling to allow fuel companies to dredge the contents of my wallet to pay for their high price of "premium", non-alcohol fuel. I use E10 fuel conditioner in my fuel when I store the Brick for six months during winter. No fuel separation or its resultant corrosion have occurred during the 90,000 miles of my Brick's history.
I admire your approach to the preservation of your Brick and am glad you have posted here about it.