E-Bike: All Electric Bicycle, No Pedals!
My daughter might have been the only person in Maine and perhaps the USA or even the world to take an ebike with no pedals to school. She is a trendsetter and a generous person. She didn't mind being unique and she enjoyed letting others at her school try it out. She is now working at a very successful start-up company called BookBub.com and she is involved with starting up a new company that sells audible books called ChirpBooks.com.
One of my design goals for this ebike was to keep the center of gravity as low as possible. This would ensure a safe, smooth and fun ride. After some thought there was simply no other place to put the heavy lead-acid batteries except below the rider's feet. The pedals had to go. But one 300 watt hub motor would not be enough to propel the bike up some of the steep hills we have in Orono Maine. So I purchased another hub motor for the rear tire. The next goal was to develop a way to install 60 pounds of batteries on the bike.
I
bought some galvanized angle steel and made a tray for the six 12 volt
12AH batteries. You can see part of that black angle steel bolted to
the bike frame where the pedal axle would go. I then attached the back
of the battery tray to the rear of the bike with turnbuckles. I covered
the battery box with 6X6 square rigid board used for covering 4X4 wood
posts and cut it in half so that they were L shaped. These made a
good foot rest.
The elevated position of the feet on the battery box meant a traditional seat would have to be mounted high on the seat post. I wanted a low bike rider feel, with a low center of gravity, so that the rider could sit back comfortably and enjoy the ride. I opted for an old-fashion Sting-Ray bicycle banana seat. I mounted it by using two hollow rectangular aluminum bars as shown in the above picture. The seat also serves as a partial splash guard above the rear tire.
I
thought about designing a single control for both hub motors but ended
up with this simple solution. One of the throttles is a twist grip and
the other is thumb throttle. They both mounted nicely on the handle bar
and twisting both at the same time is a natural action.
The
last step is to turn the keys to start. Both hub motor kits came with
key switches. I mounted both on the handlebars and I was ready for a
no-sweat and quiet test ride along the streets of Orono Maine, to the
University and back. One thing to be aware of though, the ebike is very
quiet and fast, you are sitting low and you are not pedaling, so cars
and people might filter you out of sight when they look your way.
Basically you are in stealth mode. I almost had a police car cut in
front of me when I was travelling along the side of the road on one of
my first rides. I might add a flashing bright LED light to the front and rear just to be safe.