1979 1000sp fuel taps

Hi all might be a silly question twin fuel taps turn em both on or just one, both have reserve will one tap empty both sides,my Commando has twin taps but one is main and one is reserve,just asking.:thinking:

The tank sits over the frame, when it is full it doesn’t matter which side you use as there should be a crossover so both carbs are fed . When the tank starts to empy if you use obe tap only one side will run onto reserve early. I have always used both taps, not sure what advantage you would get just using one tap, apart from a larger reserve.

Cheers. Thanks :+1: