[changzuki]

Originally Posted by sendler

You are thinking racing, not fuel economy. Generally in real world driving, lighter can be better because you do have to use the brakes occasionally and no one is going to religiously PnG. But with PnG adding mass to a grotesquely over powered vehicle such as most motorcycles will improve FE. Your comparison with human power is forgetting one thing. The brake specific fuel consumption of a combustion engine is terribly inefficient over all but a small spot on the map. The difference between the optimum operating range at 35% efficiency and the average of 15% is huge. Soaking up the energy that is delivered at the optimum range is difficult. Even the meakly powered CBR250R will absolutely average better FE on a real world cross country trip with 250 pounds on the bike instead of 150 if Pulse and Glide is used. Stressing out over reducing total mass in a hypermiler is a big misconception. Performance suffers with added weight, but FE not so much if you don't touch the brakes.

Back to the bikes. A human powered vehicle weighs 5 times more than a road bike but goes 3 times as fast due to the better aerodynamics.

Sorry, rant over. Replacing the lead battery in your pick up truck with lithium in order to improve the fuel economy is a huge waste of money.

sendler,
After reading your postings, I believe You are the perfect candidate to put your theory to its next test!
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As an example, what would stop you from doubling your total external added weight to the same bike and then revisiting the Green Grand Prix? Since you have a baseline to work with (past results from the Green Grand Prix - same course - same bike - same driver), and already know the course (should be an advantage), you could do all of what you're saying and then publish the results. This is a golden opportunity where you may even be able to greatly exceed your current Green Grand Prix numbers.
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There is likely a limit as to how heavy you could make the bike but with different sets of real world numbers maybe we could see what the cut-off point is and possibly come up with a forumla where "X" added weight can yield "Y" gain in mpg. Also, if the extra weight is general in nature then this may be the easiest and most cost effective way to raise mpg. Would you do this in the name of science and ecomodder camaraderie'? What say you?
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~CrazyJerry