I have a bike with all dc accessories.Headlamp,taillight,gauge lights etc.When turning on the key on a battery with only 12.2 volts what is the typical voltage drop.The headlamp is an automotive 30 amp.
With that much load, there’s definitely going to be considerable voltage drop. What is the no-load, fully charged voltage on the battery? And what is the amp hour rating of the battery? 12.2 doesn’t sound abnormal for that load.