According to RAW (I think):
Dirt bike: Travel 6/4; Fuel Cons. 0,5
Road: 1 shift, 6 hexes, 3 l
Off-Road x1: 1 shift, 4 hexes, 2 l
Off-Road x1/2: 1 shift, 2 hexes, 1 l
If using the alternative interpretation:
Road: 1 shift, 6 hexes, 3 l
Off-Road x1: 1 shift, 4 hexes, 2 l
Off-Road x1/2: 1 shift, 2 hexes, 2 l
Sure, the assumed RAW rule is probably how you should do this.
Shouldn't that be:
Dirt bike: Travel 6/4; Fuel Cons. 0.5
RAW:
Road: 1 shift, 6 hexes, 3l [0.5l/hex]
Off-Road x1: 1 shift, 4 hexes, 4l [2x0.5l/hex]
Off-Road x1/2: 1 shift, 2 hexes, 2l
Alternate:
Road: 1 shift, 6 hexes, 3l
Off-Road x1: 1 shift, 4 hexes, 4l
Off-Road x1/2: 1 shift, 2 hexes, 4l
The RAW interpretation seems to me indeed the closest to how it works IRL.