You might check with your DMV (look through their website) about a lien sale on the bike. In California at least, if a vehicle is abandoned on your property, you can charge storage fees, and then put a lien on the bike for the storage fees. Send a registered letter to the last owners last known address, and if you have the letter returned, or receive no reply, the bike becomes yours. More time consuming, but lots cheaper than a new frame.
Actually, considering what it'd take to transfer everything to a new frame, not any more time consuming.
Actually, considering what it'd take to transfer everything to a new frame, not any more time consuming.