Hello Silent Hunter,
if you're not in desperate need of your Big as a daily driver: take a short time and wait for comments of wiser fellows here. You probably save some money. As far as I understand it fuel always goes through the pump although it's only needed when the level of fuel in the tank is lower than the position of the carbs. But I can't tell you if there is also a flow of fuel if the engine is not running. Me, I would expect a flow as the SR 41 models suffer from fuel in the engine-oil if the rubber seals of the needle-valves are shot and you forget to turn the petcock to 'off'.
Sorry as I can't give more advice. This is what I know up to this moment. I'm also fiddling in this area as the right half of my tank usually stops providing fuel to the left half and to the carbs if the level gets lower than 2/3s of it's contents. Thus I'm carrying around some 10 litres of fuel for nothing ... At the moment I'm adressing this phenomenon to a partwise blocked fuel-pipe in the tank.
Kind regards, Bambi
'Find me kindness, find me beauty, find me truth ...'
(Dreamtheater, Learning to live)