The two upper subframe bolts (search for Subframe Bolt Replacement) are usually replaced but they work very well to replace the rear muffler bolt (lost returning from San Diego) and the rear tail pipe bolt (lost going to San Diego). They are still on my KLR.
There is also a bolt behind the rear master cyclinder that attaches the tail pipe to the muffler. This bolt will vibrate loose usually because most new KLR riders don't know it is there. If it is there, remove it, clean it, Loctite, torque, and reinstall. It should be good after that.
2005 KLR 685
2015 Yamaha Super Tenere ES, 5/23/2015
2012 Yamaha Super Tenere; Purchased 7/30/2011; Sold 5/23/2015