I've just "sold" my bike but now we face the problem of how do we get to the licence office (30 kms away) to change the paperwork. If i drive my bike there how do i get back. I can't trust him to ride my bike there in case he shoots off without paying. He won't pay until the paperwork is done. Never easy in Thailand.

taxi .......?

or meet him there with your bike ad ask him for a lift back (if you feel safe being his passeneger )

^^ Yeah, some people make an elephant out of a fly.

Think of it this way. How many motorcycle rental shops are there in Chiang Mai? Bunches. How many rent bikes that are 250cc or larger? Quite a few.

So -- How do they protect themselves against everything that has been discussed in this post???