A locking, solo trunk box bolted to the passenger seat is convenient for carrying stuff even if your 40mph average won't allow any aero mods to help the fuel economy much. A solo box can be long and skinny for an aero improvement instead of the cube shape of most normal moto trunks. You could make something out of plywood with a taper or just buy a large tool box. Anything long and narrow you put behind will be an aero inprovement
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Shop Centrex Plastics, LLC Commander 25-Gallon Tote with Latching Lid at Lowes.com
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How often do you have to exceed 65mph to keep up? A Honda PCX150 is the ideal stop and go commuter. No shifting. No chain to lube. 300 pounds and ultra low cg is easy to handle in and out of parking spots that no other vehicle can use. And the best part, 100 mpgUS at 40 mph. You can buy a hardly used one right now for $2,000 and it will last forever. I have 17,000 on mine and with electric heated gear, I ride it 75 miles every day there is no ice.
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http://powersports.honda.com/2013/pcx.aspx
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The new Yamaha Smax will be a little faster on top speed and a little less fuel efficient if anyone needs a 70 mph cruise capability.
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http://www.yamahamotorsports.com/spo...20/0/home.aspx
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