I have zero problems with the chain on my 03 B12. I set it when I install it and chain slack doesnt change between then and when I have to replace the rear tire. Basically, I only need to adjust my chain once every 6500 miles or so. I use a dry teflon rubber lube that keeps the "O" rings pliable, stops rust, and doesnt sling off or hold dirt/grit. Put the bike on the centerstand, set the chain tension with the adjusters, tighten the axle nut and then lock down the adjusters. Maybe wipe the chain off every month or so with a dry cloth. Couldnt be easier.
Blue