I have experienced a problem that I think may be of interest to K100RS owners.
I have a 1985 model European delivery which has only 46,560 km which is all main road touring. When returning from a weekend touring, developed a fuel leak from the base of the tank. In effect it had split around the locating peg.
When I finally got home I examined the area critically and found the rubber grommet had squashed which resulted in the peg coming into contact with the chassis rail. Thus with the weight of a full fuel load and the Bagster tank bag loading up the grommet allowing the peg to push up into the base plate of the tank and therefore developing a crack.
I've spoken to BMW Australia to highlight the problem and its now off to the nearest dealer for resolution.