[pavulon]

I replaced the jets and needle in my Honda XR last winter because it came from altitude in Montana. Prior to doing this, fuel regularly overflowed onto the ground if the tank petcock was left open. I fiddled with the float a bit while I had the carb apart and after reading and watching YT it occurred to me that I would want the fuel bowl to be as full as possible without overflowing which no longer occurs. I cannot think of a down-side to having the bowl full of fuel but as you stated, there is a potential down-side (lean running) to having it closer to empty.