So with the engine running, if you switch main beam on, engine dies instantly
What happens with engine running and dipped headlamp?
With engine not running do both dipped and main beams work ok?
On the diagram, it shows the bike has no headlight on /off switch, so they are permanently on this agrees with what you stated in your initial post, that they are as you said "running lights", According to the diagram the only time they go off (Whether dipped or main beam) is when the starter button is being pressed, Which does make sense as maximum power from the battery would be needed to turn the engine.