The pump shouldn't run for 5 sec every time you turn the key. If the bike hasn't been started for a while, couple days etc yes as it's refilling the float bowls due to evaporation, but not if you've just stopped it parked it for couple hours, at the very most a couple clicks. When was the last time the fuel filter was changed? These become restricted over time and it takes longer for the pump to get return feed from the carbs so they pump longer. Have you get any leaks, smell of fuel etc? It's also possible the pump has had it's day.