Well, the next question I would have is this:
If you settled the lein with the bank wouldn't they be obligated to send the title to the person who had the lein (which you are no longer able to locate). Why would they give a title to someone they have no dealings with and no legal paperwork saying you own the bike?
You might have to check with your attorney and see what rights you have to file paperwork of your own if you want to keep it in one piece.
Once you do that the bank knows where it is at, and either they'll come pick it up or money will fly out of both of your pockets one way or another to keep it...either to your attorney, or to the bank, or to your friend down the road you borrowed $2 from when you were 13 years old.
If you go this route, no doubt the previous owner will be brought into the conversation. Do you have a bill of sale at least so he can not claim it to be stolen?