I would take a money order or certified check and upon agreement on the sale he and you go to the bank together and deposit the check and keep your transaction receipt. At the same time, once the bank has accepted the check get the title transfer notarized.
I bought a Road King without riding it years ago. I've also refuse to let someone ride a bike I had for sale and he walked away. It didn't bohter me one bit. If the buyer gets to know the seller enough to trust him, see the maintenance records, the condition of the bike, start it, run it, and good detailed once over I'm ok with it. Bikes are very different than cars in the test ride respect. I understand that as both a buyer and seller. If a buyer dosen't understand that then he has not been around the bike world very much. There are many, many horror stories about bikes that don't come back or don't come back in one piece. On the other hand if he leaves a $20k+ vehicle in your driveway with valid registration and keys and seems like a honest guy that has the ability to stand behind his mistakes.... But remember that the most honest, respectable guy in the world can total your bike and even get killed doing it. Again it's not like turning over keys to a car at all IMHO. There are many sellers that don't let someone ride away on their bike under any circumstance so you won't be alone in that respect.