I was out riding with another SDAR guy this weekend and felt something give way shortly after leaving home. When I rode up to the meeting spot, we could tell the bike was super loud (well...louder than usual). I thought I'd lost a header bolt or the exhaust was loose somewhere. But a closer inspection revealed that an entire piece was missing. Just gone. (It was the elbow between the header and exhaust like the below photo.)
A little research showed that this is fairly common, unfortunately.
http://advrider.com/index.php?threads/ehh-lost-half-an-exhaust-header.881020/
Instead of welding/repairing it, I may just buy a used set and replace the entire thing.
Has anyone experienced this? Ideas on how it happens? There was no indication it was broken before it went bye-bye.