This route is really something. Glad that you gave us suggestions on this. Everybody was smiling upon reaching destination. Thanks again. Will head back to Chiangmai soon and then to Nan, probably you have another fun route? 3
When you come back into Laos from China at the Boten border crossing, head south in Laos to the Laos Muan Nguen/ Thai Huay Khon (Nan) border crossing. It's a land crossing with no ferries or bridges, you will have to cross the Mekong in Pakbeng by ferry on the way.
Then from this border crossing you can ride the legendary R 1148 back to Chiang Mai, which is one of the premier roads in Asia, great surface and race track curves.