I ride a 2011 Honda CBR250R with the air box lid removed and 7% longer gearing (plus 1 tooth in the front). I did 134.99 mpgUS at 45 mph on the track at Watkins Glen during the 2012 Green Grand Prix. No aero mods other than an over night duffel bag tied down on the rear seat, "plank style" and a tank bag stuffed with a sweater to lay on in a moderate tuck. It was a 3 hour timed run with 2, 3 minute breaks. I used full on Pulse n Glide with Engine Off Coasting. A favorable tail wind let me coast all the way down the front straight in addition to 2 places after the climb on the back of the track. I guestimate that the engine was off 25% of the time. It's not great for the trans but can give you a big number in competition.
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14% longer gearing installed, I went to the 2012 Ohio Vetter challenge with 60 pounds of camping gear in a 16" x 30" duffel on the back and got 100 mpgUS, 2.35 liter/ 100km, 42.5 km/ liter.
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With good weather I am between 90 and 100 mpgUS all summer long on my 80 mile, 65 mph round trip commute. I should be able to do better if I ever get around to getting a tail built.
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