At the risk of bringing down the wrath of the mods for populating the forum with F this and F that, I have read as much as I can find and discussion about one of the major design differences between the F658 and F800 seems thin on the ground. We are about to decide between the two and this is the final piece in the puzzle. Given that the engines on the two bikes are essentially the same, the question has to then be asked: Is the F658 cooling system under engineered for a hard slog in heavy going on a hot day? Or is it more a case of increased potential cooling from a larger and therefore heavier radiator on the F8 is just more for the sake of more and not necessarily better? Has anyone actually caused an F658 to overheat in sand for example? To date I have not read any reports of it happening and therefore have to wonder if the increased cooling of the F800 is actually an advantage in the real world.