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The was my last and best attempt at an electric bike.

I bought a motor, controller, throttle, and display from a company called ebikes.ca (now appears to be "Grin Technologies").  Working directly with Justin (the owner?), I picked out a brushless hub motor and "pedal first" controller.  These controllers do not use the hall effect sensors to detect rotor location so they need a small amount of rotor motion in order to determine the commutation location.  It makes for a simpler install but is a little annoying to get started.

The display is called a "Cycle Analyst" which is a really cool device that shows you voltage, speed, current, and integrated energy.  You can see some photos above.

My battery pack was based on NiMH cells in the "sub-C" size.  These were arranged to output 72V nominal.  I added some cooling fans that were active during charging (the charging of NiMH batteries is exothermic).

I had one cell fail as a direct short which caused the parallel cells to heat, swell, and then catch fire.  That was exciting when I was on my way home from work!

I also had lots of adventures with my excessively conservative employer not allowing me to plug in my battery pack to charge while at work (people are strange!) but overall this bike was great.  I probably put 1000 miles on it.

The end came not due to any technical failure but a move out of the country.  I still have the motor, controller, and display.  I recycled the batteries as they were used a little too hard to last.  Maybe someday I'll resurrect this beast :)