BMW has been using a range indicator on their motorcycles for the past few years - with mixed results. The early versions started counting down the miles left once you reached and estimated 50 miles of gas left in the tank. That worked fine for me, because I ride at a steady speed all the time, but not so much for may other people - including the motorcycle press, who had a tendency to run out of fuel with 10 or 15 miles left showing on the computer. Since then BMW seems to have dropped the countdown feature and just lets you know when you have reached your "reserve" fuel at an indicated 50 miles of range left, based upon your average mileage during your current ride. They then show the number of miles that you have ridden since hitting "reserve". I am not quite sure how the latest models handing the issue, but it can be a real head-scratcher for a designer, as you can never really predict what an owner is going to do with your bike in the field. All you really know is that if they run out of "gas" and have to start pushing, they are going to be really unhappy - not a good thing. So the conservative approach to estimating range usually wins out.
