For some years, I had been investigating buying or building an Ebike as a replacement for for most of my car-as-driver-only journeys from the city to Upper Sturt, a sort-of "reverse commute". It was in doing this research that I first stumbled upon AC.
My investigations revealed that for my purposes, a mid-motor, chainwheel drive arrangement would be best, as this makes the bike gears available to the motor, unlike hub motors of any sort, and, incidentally, unlike all petrol motor kits, whether street-legal or not. (An American company, Sick Bike Parts, now does a conversion kit so petrol motors will run through the chainwheel.)
The day I decided to purchase a chinwheel drive Ebike, from E-motion, was the day that company folded. So then it was back to the idea of building one myself. After discussions with Mic Chapman, I decided to go for a 36V 200W kit from Cyclone (in Taiwan), and build the Lithium Ferrophosphate (LiFePO4) battery from a kit sourced in China. The chainwheel set was selected not for speed, but for hill-climbing ability.
I got a 27" mixte frame from the Community Bike Workshop. Gary of Star Cycles (Elizabeth) added V-brake lugs to it, and supplied brake levers, derailleurs and a few other bits and pieces. Other parts, including the wheelset (ex Mongoose), were sourced from my own stocks. The back wheel (originally from the Mongoose, but not the original wheel) is not fit for regular service (severely worn braking surface) and will be replaced.
The frame and the aluminium battery case were powder coated by Central Powder Coaters of Keswick.
I have spent odd bits of time over the last few weeks building the bike at our place in the hills. It was test ridden, as an ordinary bike, a couple of weeks ago, and, as a bike, it rides very well. I made a short test ride with power assistance on Wednesday 24/04/2013. On this test ride, I was able to go up a hill that I have not been able to ride for more than 10 years.
On Anzac Day, I caught the bus up to Crafers, and walked down to Upper Sturt. From there, I rode the bike home via Cherry Plantation Rd in Belair NP, Gloucester Ave Belair, then down through Panorama and Colonel Light Gardens.
Power assistance was used only for uphill sections until after Springbank Rd, when, feeling somewhat lazy, I used the power to supplement my pedalling until home.
Today, Friday 26/04, I rode the bike from home to Elizabeth West, but I cheated on the way home and used the train for some of the journey.
Frame: modified Liesure Cycles 27" mixte.
Motor: Cyclone, with external controller, 36V, 200W.
Chainwheel set: Driven wheel 48t, driving wheels ("normal" gears) 44t/32t.
Rear cluster: 7sp, 11-28.
Battery: 36V nominal LiFePO4, 15Ah (540Wh capacity = "fuel tank size"). This is a very big battery.
Weight: Front 14kg. Rear 15kg. Total 29kg.
Maximum grade climbed (so far) 18% at 11km/hr.
Maximum speed with power**: Pedal start, then motor only: 31.5km/hr. Pedal start, then keep pedalling: 35km/hr (at which speed I am spinning out on the available gearing).
**Flat ground, little wind.
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