Dipped and main headlight erratic

[DJN]

  Just as the nights are getting darker ,my headlight is refusing to illuminate as it should: 
Ignition on and running lights come on,, but no dipped beam.
Engine started and, after  30 seconds or so , dipped beam comes on.
Sometimes main beam works when dipped doesn't...  sometimes neither  . 
   Fuse  checked out OK.   Have cleaned the  contacts on the headlamp  plug (DUPLO tytpe connection).
Wiggling  connecting wires about  has no effect  , but sometimes  moving the handlebars sharp right
causes dip beam to  illuminate.
   Any pointers on how to  test the lighting circuit  would be gratefully received - yes, I have a multi-meter.

[Jletyxa]

First I advise you to check the voltage on the battery. Next, the generator. If the problem is not with them, then the lamp itself.

Each lamp has its own lifespan. Therefore, if you find the same lamp, just check that another lamp is working. If it works well, then the problem is the lamp. If not, then the wiring. I advise you to install Bi-led H4 with a lens. Great stuff.

[DJN]

 The problem was corrosion in a wiring harness connection
that caused  the plug to  the lamp to overheat - its voltage was measured  at 18V.
A replacement plug was required .
 Previously, spurious activation of the FI warning light  may have had the same cause.

Seems like the electrics on these bikes aren't up to usual Japanese standards.