Fuel taps - on or off?

Off always.

Although on my Funduro even with the tap off, the bastard recently puked all its 17litres of fuel over itself and then the wooden garage floor as the tap had failed. New tap and carb rebuld kit now installed!

Tap off. is suspect that leaving taps on gives rise to the yellow fuel stains that some bings have as a certain anmount of fuel gets past gaskets when left on for long periods of time.