rmezei
Member
The petcock reserve system was not infallible. Assuming your petcock was located on one side of the tank, when you got down to the level of the main pickup tube, leaning the bike left and right would slosh more fuel into the main upper pickup tube. Aggressive weaving or curvy road riding kept sloshing fuel in the carbs, even though when the bike was level the fuel was below the main level. When you finally had to switch the petcock over to reserve, there was less fuel left in the tank than you realized. I ran out of fuel one time in the '80s in the boonies because of this. I was able to borrow some from my riding buddie's tank.
The NC display flips back and forth between bars due to the fore/aft level of the tank. Braking or going downhill lowers the readout. Accelerating or going uphill raises the readout level. The position of the sender and the odd shape of the tank is probably the cause of this behavior.
I don't know - my 2017 has a reserve counter that starts at 0.0L used and it goes up as I use the litres and I know it has 3L from the owners manual... then at the same time also shows me how many km's I used on the 'reserve' fuel.