I bought a lightly dropped 2005 K1200S in August of '05 with just 85 miles on the odo from a customer, repaired it and by October of '07 had ridden it nearly 37,000 miles. I rode it fairly easily for the first thousand miles, changed the oil then gave it cane on a regular basis. I switched to full synthetic oil after 6,000 miles. All the services were done per the book, by me. In that time I replaced an ignition coil (there are four), had the airbox recall done, and replaced a broken petrol cap hinge under warranty. Nothing else went wrong. I spent a month riding it in Chihuahua & Baja Mexico and the US desert South West, travelled across the Rockies and the Cascades and rode it daily to and from work near Tacoma/Seattle, Washington as I didn't own a car.
The Canadian I sold it to (when I returned to OZ to live full time) has it still and has covered well over 100,000 miles all up. We email one another a coupla times a year to keep up. He has since replaced two more ignition coils and had an ABS fault. It doesn't burn oil. That's our experience with it.
There have been minor issues with the steering dampers feeling tight, and ball joints binding, causing the steering to feel slightly 'weavy' in the Duolever front suspension, as well as the few that Inge mentions, and some early models had balky gearbox/clutch basket issues, as well as a rear suspension linkage 'dogbone' recall which is paid for by BMW. They are not bulletproof but I'd load one up and cover some miles or kilometres, no worries, and I did.
As much as I like my '87 K100RS the K12S will accelerate far harder, run incredibly smoother, brake so much better and just feel sweet
over-the-road as compared to any older K bike from the first years to the
last K1200RS/GT. I'm going back over to the States for several months and might just try to find another one to ship back home to OZ, they're that
good. I'd like a K1300S this time since the mods done to them have refined the machine over the original across-the-frame-engined K12 series.
Lolo Pass, Idaho/Montana.