I never thought this kind of maintained highway exists. Painted lines, but the absence of central marking means it’s effectively a single carriageway, single lane highway. This is in Yan, Kedah. First time discovering this, personally for me, is quite bizarre. Well, residential highways in newer housing estates have two lanes minimum.
Street level photos show Penang and Johor have this kind of road as well. Luckily this is obviously a highway=unclassified.
Some FELDA roads in Johor (with JKR reference codes) looks exactly just like this - from OpenStreetCam (Sepuluh Q drebar e-hailing kita).
A lot of kampung roads are like this. Width is around 3.2 meters I think (from road resurfacing project signboard in Merchang - don’t know whether it is a JKR standard). The roads are too narrow to paint center line.
That’s very narrow indeed. But I’ve found roads in Thailand such narrow (or even less - it’s hard to find out when the plants are trying to grow over it) with a central line. So, actually two lines each wide enough for a bicycle or motorbike, but a car would require both lines (and I am sure it was not a two-lanes cycleway).