The best streamlining might get an electric motorcycle up to a top speed of 75 mph without adding a transmission. And get it down to 90 Watt hours per mile of consumption at 65 mph/ 105kph. A 72v 100ah would be difficult to fit. The A123 Amp20 pouch cells clones are the best right now and being sold direct from China for 1/3 the retail price. $25 each in quantity. $2200 for the cells at the wholesale price. The finished size would be two rows of 240mm x 180mm x 320mm and weigh 100 pounds / 45kg. You don't want to carry it around and it barely fits. A similar battery from GBS cells would be much larger due to the nice cases and cost $4000 with a monitoring system and charger. These cutting edge batteries would provide a usable range of 60 miles/ 100km at 65mph using a gentle 80% of the capacity and charge in 5 hours from a normal 110v USA electrical outlet for $.80 . With perfect care the A123 cells should retain 80% of their original capacity after 3000 cycles.
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I am starting a new project for an e-bicycle conversion using a hub motor at 72v/ 20ah on a fully faired recumbent. My goal is 40.40.40.
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40 mph average speed, 40 mile range, 40Wh per mile.
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Actually, I will need to hit 30Wh per mile to make it to work without adding a second, $700 pack which might mean an average speed of 35mph. I bought the bike and it will be easy to streamline with an oval bubble for the nose and a fabric body back to the tail.
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