Consider taking some petrol and a battery and see if it will start, if the sellers are agreeable.

This smells like baitfish stuck on a boat seat after 2 days in the sun.  

Ask the guy if he has an active title in HIS name so he can transfer it to you at the point of sale in front of a notarizing loan officer at your bank.

If not, then he can't sell you squat ....  he doesn't own it.

Accept no entanglements with a "promised activity" by any third person -- when it doesn't happen you are left holding somebody else's property which will be returned to them as soon as it shows up on the law's radar with any attempt to get title or register or get plates, etc.

And you will get squat out of it, except a citation and a fine for having had somebody else's bike in your posession.

Worse yet if the title is in the dead guy's name, not even his heirs or parents could sell that bike without it going through escrow (inheritance legal BS) and then a new title being generated at considerable $$$ cost (18/20 years worth of back taxes) and delinquent taxes fines & even more DMV BS and then finally the generation of a new title in the new inheriting owners name.    

Then the bike can be sold to you.

You are likely getting played by someone with a dead bike that belongs to a dead guy that they CANNOT gain title over.    

Or else it is a stolen hot bike that if you wrote down the serial number on the frame to ask DMV about it the seller would get all sorts of upset about that -- they know what it is.           ie NOT THEIRS TO SELL .....

Don't be a mullet ....  

Sage advice up there. Take that guy and the title to the dmv & make sure that title is good if youre not 100% satisfied that it is,
Maybe you could
Get a hand written bill of sale, signed by the guy & include in the bill of sale that the title is clear & in his name & he can legally sell it & you can transfer the title into your name using normal, standard methods OR he will refund the $$.
IDK how legal all that is, it sure Sounds like a decent deal.,. with a bit of a potential Gotchya attached.,.,

The bike has been sold, problem solved Maybe I missed an opportunity or maybe a headache, either way it's done and someone else's worry now. The guy never replied about title, he was slow to answer and short on his email, something I dont really like to begin with. But there's always the next opportunity, thanks to all.