I recently increased the power of my Stoked Big Dummy by setting it up to use two 36v batteries in series rather than only the one 36v battery. (“Stoked Big Dummy” means a Surly Big Dummy extra long bike with a Stokemonkey electric motor.) The change required purchasing a more robust motor controller from the fine folks at ebikes.ca. I also had to open up the controller and solder some beefier resistors in there and make some other modifications. But the result has been amazing. My bike is now very responsive and can easily accelerate to 20mph in a few seconds, and go up hills at 15mph without pedaling. Normally in this blog I rail against speed, but I am discovering that this moderate increase in speed increases the utility and safety of my beloved car replacement vehicle. I can now go on single-afternoon 100-mile trips by bike without it being a big deal “tour”. And I can more easily maneuver in traffic and join the flow. True, I’m now using 20 watt-hours/mile rather than my usual 10 watt-hours/mile, but still nowhere near the 1200 watt-hours/mile that a car uses.
I won’t deny it, speed can also be fun. I recently put together an ebike for my daughter. In the photo above you can see that the bike has a big black front hub. That’s the motor. The batteries are in the bag on the bike rack. Her first ride produced in her the legendary “electric vehicle grin”. She said that her bike was “like a car disguised as a kid’s bike”. She instantly recognized that her new ebike would give her a basic freedom that is denied to kids in our society: the ability to use roads for transportation. Kids in our society are taught from the moment they can walk to stay out of the road. No wonder then that kids must rely on parents and school buses for transportation. No wonder we have an obesity epidemic in this country. The ebike, and the EV grin it causes, may change this sad state of affairs.
I thought this recent post to the Endless Sphere ebike forum by icecube 57 captured the “EV grin” phenomena that is currently only shared by hobbyists but may soon be experienced by the general public as ebikes take off. You can read the original post (along with video) here.
“In other news Im very suprised at the power of this motor. My neighor just moved in her bf. I came home to find them socializing with my wife in the garage. The conversation shifted to my bike. He was like ill try it later. I said you are going to try it now. He gave in. I started him off in Grandma mode. (20mph legal restricted) He was excited about that. The controller still dumps 3500-4000w off the line but it tapers off quickly and he proceeded to take my bike up the huge as hill on my street that I will stall on in grandma mode and it took him up the hill without stalling un assisted maintaing about 15mph. Which I cant even do unless I have a running start. He is about 120lbs lighter than me so I can understand it being easier on the motor and controller. He went around the block and came back. He said take this out of grandma mode. He had a grin from ear to ear…Its one thing to ride your own bike but to see someone else riding it with EV grin hauling ass at top speed in traffic like its a motorcycle”
For the record I only have a temporary interest in riding an electric motorcycle, until the grin wears off. My ultimate goal is to build a lightweight (200 lbs.) narrow (42″) slow (20mph) passenger-carrying “car” that falls within the legal definition of an ebike. I couldn’t see myself succeeding with 36v. I can definitely see it happening with a 72v machine.