"It's on Koh Samui according to the photographer on his Facebook page." I think some context was lost in the Facebook translation, and my Koh Samui guess was wrong. The photographer did talk about taking photos on Koh Samui in his thread, but I now think Dodraugen's query road is the same as Moor66's "parachute mountain road in Chonburi." The clothing is also a better match—not many riders on Samui wear full face helmets.
The "parachute mountain road in Chonburi" is the access road to the Khao Ang Kaew Viewpoint at 13.16246,101.41687, at about 270 m elevation. It is partly visible in the satellite view but the road is not included in Google Maps nor in Open Street Maps.
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Watch these two short clips and see if you agree this is the same road:
Khao Ang Kaew viewpoint · 5C68+WPX, Bo Thong, Bo Thong District, Chon Buri 20270, Thailand
Photos of the viewpoint and road from Google Maps:
Khao Ang Kaew Viewpoint
In the Google Map photos you see pickup trucks at the viewpoint, some of them carrying paragliders and their equipment. That road in many places isn't wide enough to pass a truck, and in many of the same places the road too steep for a motorcycle to stop, especially going up. A significant risk on this road is encountering traffic blocking the road, and losing momentum.
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And the best photo of all:
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