Going for a Spin


Probably the third test ride.  I've still got the ridiculous wooden chain tensioner but I'm finally using the lithium-ion battery packs I built.  Right about now is when I started learning the voltage/current rule:  Voltage directly relates to the speed of the motor, and current directly relates to how fast I can get to that speed.  Since I didn't want to put the batteries in parallel I decided to use the gearing to optimize for the torque I wanted with the batteries wired in series.  This way I always have the torque on demand, and if I want the bike to be faster I just add more batteries in series (increase the voltage).  The side benefit to this is I can configure the bike for city driving with less battery weight and highway driving with more battery weight.  Think of it like a smaller gas tank that reduces the weight of the car when you don't need to travel long distances.

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