My K1200LT is a 2006 build.
I reckon that I just saved myself a nasty accident and here are the details that I hope may prevent others from even coming close to what may have occurred.
The bike has done 30,000 kilometres and had a new clutch at 10,000 due to an oil leakage issue.
At 30,000 I was about to fit a new rear tyre and decided to remove the wheel myself.
When I did I found the base of the rear shock bent to hell and almost no bolt left at all.
There was about 25mm (one inch) of the bolt remaining with the nut still attached and the head along with the rest of the bolt had gone to god or whereever bits that fall off go.
I removed the shock after having to use a pry bar to release it from the swing arm as it had wedged itself in place and this is probably what stopped the rest of the bolt falling out leaving me with no rear suspension in something less than a heartbeat and as I was about to leave on a ride through the Snowy mountains I do not even want to think about the result.
I managed to repair the bike in readiness for my 0700 departure next morning and used a grade 12.9 cap screw with a self locking crimp nut to secure that bottom mount.
My further investigation has revealed that during some but not all production BMW fitted self locking nuts to the original grade 8.8 bolt but at sometime they decided that a self locking nut was not necessary and starting using a regular flange nut as I found on my bike.
The top bolt has apparently used a self locking nut all through production of the K1200LT.
Why anyone would remove the self locking nut from production bikes leaves me bewildered to say the least.
You cannot see this bolt whilst the bike is fully assembled and I recommended replacing the nut with a self locking nut if your bike has a plain nut as did mine.
If the nut comes loose and the bolt loses it's torque then it will fatigue as I suspect mine did and break.