Muffler Repair and Photos
I bought my R850 used with about 19,000 miles. Judging from the rusted screw and bolt heads, the previous owner did not garage the bike. Perhaps this also had an effect on the muffler baffles. Whatever the cause, the baffle is rusted out right where it exits the muffler. This photo is of the end of the muffler. The rust colored part is the inside of the tailpipe. The black gaps are where the baffle/pipe has rusted away from the stainless steel case.
BMW has changed this design a bit, and for good reason. The muffler/catylitic converter is stainless steel. However, in a bizarre twist, the baffle inside the muffler is regular steel. I would love to know why. After market mufflers like Staintune are stainless inside and out.