I have a motorbike with a wet battery. I use its electric starter to start the engine.
Is there any research done by others before to prove which one of the following makes the durability of the wet battery shorter?
Assume the motorbike is well-maintained and still in factory default settings.
Case 1: The lights are turned on before pressing the electric starter button until the engine starts.
Case 2: The lights are turned on after pressing the electric starter button and the engine starts.
Note: I am only interested in the scientific data because without it, I can say nothing to my debate partner.
I said to my debate partner that both methods are fine. However, my debate partner said the first case makes the battery life time shorter. He cannot give me the proof as well. :-)