Beware of spoilers regarding Mad Max: Fury Road.
After they meet the Many Mothers, Furiosa claims they have bikes that could run for 160 days. Somehow, I don't see how bikes could carry so much, but lets assume they could have some trailer on them with supplies or a sidecar or something.
160 days * 8 hours driving * 100 km/h = 128,000km. The circumference of the Earth is about 40,075 KM. So they could go around the world almost 3 times. But Max is sure there is only desert wasteland forever. Surely there can be places on Earth without those savages, some place healthier, maybe green, maybe with clean water. With so much driving range, they could explore anywhere they wanted.
What is the idea of this plot point? Was 160 days a gross overestimation by Furiosa? Is 100km/h over 8h/day too much for them in the desert? Even at only 50km/h, they could go around the world in 160 days.
Are there any explanations on this?
Edit: Despite Dr R Dizzle's great perspective, where 'days' measure distance by walking speed (or something else), Furiosa mentions that the Green Place is "1 long night's journey" away. They ride all night (with some malfunctions) and cross it during the night without noticing. In other words, a day or night's travel really does mean car/motorbike speed for some hours.