Bill Mills loves wrenching on motorcycles. In fact, he readily admits he’s obsessed with motorbikes. A few years ago, after seeing an alternative fuels documentary, Mills’ obsession took a sharp turn. He discovered electric motorcycles. He had to have one, but instead of buying a new Brammo or Zero, he went about it a bit differently. He built his own.
Tagged the Sensei, Mills built his bike on the frame of a $250 abandoned Kawasaki Ninja 250 that had definitely seen better days. After a meticulous tear-down and frame rehab, Mills began to craft his vision in earnest. “ This project was as much about design and fabrication, as it was about riding,” Mills says. “Not to mention that I was able to build the Sensei with all new power and drive train components for about half the cost of the least expensive off-the-shelf electric motorcycles. The total cost was a little less than the price of a new Ninja 250 and was funded by selling old stuff out of the attic and garage on eBay.”
This DIY bike is powered by 24 cells of 40 amp-hour lithium iron phosphate batteries which feed a Mars ME0709 motor. With the batteries and engine installed, Mills found that the balance and weight distribution of the bike was remarkably similar to a Stock Ninja 250. Another of Mills’ ingenious design features is an all bolt-on assembly of the battery pack, meaning that as battery technology improves, upgrading is a simple procedure.
And as to the question every gear head is asking? The Sensei can hit 55 mph and Mills says it’s quick enough to be comfortable in traffic and accelerates straight up to 50, then takes about three or four seconds for that last bit from 50 to 55. The range of the bike, which Mills uses as his commuter, is 30 miles of city driving.