I just measured it, by riding my bike until it stopped, tipping in 1.4 litres from a container and filling up 5km later (22.3 litres). My answer is 23.4 litres, from empty until the first surge up the filler tube when the tank is "full" (you can keep trickling in fuel for a while after that, Honda says not to). Bike on the side stand, and taking into account the 0.3 litres burnt in the 5km. Another squirt would take it to 23.5 litres. Honda claim 22.9 litres.
So, 424km (265 miles) for 23.4 litres (6.2 gallons) on that tankful is 18.1km/l or 42.7mpg.
The last bar on the fuel gauge started flashing at 329km, so that was when 5.2 litres was left. The owner's manual says 4 litres.
It looks as if I can hope for 90km or 56 miles of gentle 100km/h (62.5mph) riding when the warning starts, and a total fuel range of just on 400km (250 miles) at a more conservative 17km/l (40mpg).
The 5th bar of 8 turned off after 11 litres, leaving 4 of 8 on (1/2 tank), so when I see that happen I'll assume I can travel as far again as I already have, if I absolutely need to.
Now that I accurately know the tank capacity, I can verify the litres-to-empty at the halfway, last bar, and flash warning points on a couple more tanksfull, to see how consistent they are.
IanB
So, 424km (265 miles) for 23.4 litres (6.2 gallons) on that tankful is 18.1km/l or 42.7mpg.
The last bar on the fuel gauge started flashing at 329km, so that was when 5.2 litres was left. The owner's manual says 4 litres.
It looks as if I can hope for 90km or 56 miles of gentle 100km/h (62.5mph) riding when the warning starts, and a total fuel range of just on 400km (250 miles) at a more conservative 17km/l (40mpg).
The 5th bar of 8 turned off after 11 litres, leaving 4 of 8 on (1/2 tank), so when I see that happen I'll assume I can travel as far again as I already have, if I absolutely need to.
Now that I accurately know the tank capacity, I can verify the litres-to-empty at the halfway, last bar, and flash warning points on a couple more tanksfull, to see how consistent they are.
IanB