Hello, sometimes upon startup my tail light go out.
Ive replaced the stock one with a LED Tail light.
The tail light is a CPI(aprilia,derbi) original tail light.
Ive tried to run cables directly from the battery via a relay to the light, still same issue.

The tail light mostly dies on cold start up, its usally possible to restart the bike to get the tail light working again.

I recently installed Xenon headlight, could this be the issue?

Here is a video of it turning off on startup.
https://www.youtube.com/watch?v=d97nL-hdwDE