One more smoking question please

[crawdad]

I was just wondering if a bad exhaust system could cause bad engine smoking. The exhaust and mufflers on my bike are old, had been left out in the weather for who knows how long, and they are as black and sooty on the inside as any I have ever seen (not to mention a few holes). The smoke looks like oil smoke, but it stinks to high heaven. I've smelled oil smoke from bad rings, etc. before, but this smoke smells pure raunchy. My wife want even let me in the house until I shuck all my clothes (that's pretty doggone rough in the winter). I am just about ready to tear into the engine and replace valve stem seals, but am looking for any excuse not to. Any thoughts, ideas?

[CA.XSer]

rodent droppings? Such as mice, rats or other vermon? When burnt will smell like???? I can't describe it!!!!!

[schpiff]

smellin smoke

Im not sure if this helps but I too have had a couple occasions where I had foul smells coming out of the exhaust.. These are car related but probably hold true.....The rodent thing is about the most common...the next is VERY old oil (turns into fudge after time..and dont burn away too fast) perhaps someone (pickled) the engine with oil ie..drowned it with oil before storage, and the oil "fudged up" somwhere..hope this helps....
PS..wait til shes gone and let the stuff burn out..