ORIGINAL: Docroonie
I'm new......lets get that out right now. But I know a few things The Half tank lean situation is easy: The reason lies in the way we feed the carb... We use exhaust pressure, and so here it goes - The more fuel you have in the tank the easier it is for that pressure to push it out, as the exhaust gas has less air to compress you end up with higher tank PSI. As the fuel is drained from the vessel it gets replaced with more exhaust gas, however at some point (I believe at the "Step" in the tank) the rate at which the gasses are being pushed in cannot maintain the PSI due to the amount of space in the tank(larger space = more volume = too much exh. gasses needed to maintain tank press.)
It's a bad design. It would be best to have a uniform shape for this tank, the exhaust would have an easier time keeping up....
Let me know if I'm dumb?
I also think you are right, the easiest way to combat the lean is to get a new tank, no two ways around it[
]