The motorcycle chain gets a really ungodly amount of road nastiness on it. You find these things out when you clean 10,000 miles worth off sections of it.
Still need to change the oil, but I *did* get the tools I need for another confrontation with the bolt on the bottom of the oil pan. Even if I do real damage to it in the process, it's better to remove it and change the oil than to have to drill it out. princeofwands pointed out to me that things like metal shavings don't go well in your oil and you have to be really careful.