Don't believe everything on the map.
Some of these map publishers just like having as much info as they can on their maps, & whether it is reliable or not is quite often irrelevant, just so long as it sells maps. The “logic” being that the more you have on the map the more informative it is, so it must be a better map & you’ll sell more.
Personally with my maps I like to err on the conservative side, so that you don’t lead people up the garden path the wrong way & spoil their holiday. When everything works, the customer has a great time, & maybe even comes back to brag that he saw or even did some roads that weren’t on the map. This makes them feel infinitely successful, & they come back for more, plus probably tell their mates how easy it was with the right info from the right maps (& m/c guide book.)
I think the ESSO map is pretty good. The one I have is Thai only but they did have others. Think I got it at one of Asia Book stores on Sukhamvit in Bangkok. I remember they didn`t sell them at the Esso gas stations.