How to unregister motorbike owned by foreigner

Hi all, in April of this year I purchased a new Kymco motorbike and registered it in my name at the CSGT (it has NN plates). Due to some unexpected circumstances I now need to sell it, and another foreigner wants to buy it. Could someone please tell me the procedure for unregistering the bike in my name so that the new owner can register it? Thanks.

I can't tell you the procedure, but I'm sure if you went to the traffic police (csgt), they will be able to explain it.