When i took my Griso to the Arctic circle I had a 5 litre can balanced on each of the passenger pegs
The 5.2 Gallon tank on the Griso had a range of 355 KM so I ran out on the Dempster Hwy before Eagle Plains and had to add one of the cans.
I once ran my V7III Special up to 82 km on reserve, I was sweating bullets as I was on a strange road with no road signs telling me where the next town or gas pump was.