OwnerRoy Prince
Owner's Other EVseCortina v2
Electra Townie 21D
LocationOxnard, California US map
Web/EmailWebPage email image
Vehicle eCortina v3
My current project is the eCortina v3. With a new and improved motor, motor mounting system, and belt drive – the eCortina v3 encompasses the best of the previous machines.

eCortina Article in May issue of CurrentEVents Magazine

The eCortina v3 electric bicycle is a more refined and reliable machine than my first electric bike build, of two years ago. It features a substantially larger motor and larger battery pack. Also as the weight of the battery pack and all other associated electronics are located in the triangle, the weight distribution and handling are far superior in the current build version.

This custom motorized bicycle, and other electric vehicle projects under development, use high performance motors, batteries, and controllers from the Radio Controlled (RC) hobby business. These RC motors are lightweight brushless permanent magnet in-runners (magnets rotate inside fixed wire coils) and outrunners (magnets rotate outside fixed wire coils).

UPDATE: I am giving up on the RC controllers. Too much trouble, too fragile and too expensive. I am going to ebike controllers.

The hybrid electric bicycle system is designed so that one can pedal only (human power), motor only (electric power), or in hybrid mode both motor and pedal at the same time. Under hybrid running the distance one can ride under one charge is extended. However, realistically the eCortina must be considered a motor bike with human assist.

The batteries are Lithium Polymer (LiPo) basically a lithium ion chemistry variant. These batteries are sensitive to overcharging and over depletion, meaning that purpose built RC chargers and active, while in use, battery state monitoring, via a Cycle Analyst (not a BMS), are required to ensure good battery life.

I am currently monitoring bike performance and range and will post results as they come in. However, theoretically: 48v x 15Ah = 720Wh. LiPo batteries do not want to be discharged to less than 80% of total charge so: 720Wh x 0.8 = 576 Wh. If say the bike uses 30Wh per mile (to be determined but this is a conservative number): 576Wh / 30Wh per mile = 19.2 miles. The eCortina should go about 30 miles under mild riding with some pedaling.
MotorTurnigy 8085 Permanent Magnet DC
Outrunner Turnigy 8085 stock wind.
Soon to be rewound with 14g magnet wire with 10 turns.
DrivetrainThe drive systems are derived from mostly bicycle related parts and concepts. There are two BMX style freewheels to allow pedaling without driving the motor and motoring without forcing the pedals to rotate. The BMX chains employed here are strong and up to the task of propelling this bike reliably.

UPDATE: The drive systems are always being changed. Check out the website to see my latest version.
Controller eBike controllers
Various 30 to 45 amp controllers are being tested.
Batteries6 Turnigy 24v 5ah, 24.00 Volt, Lithium-Polymer
25c
System Voltage48 Volts
Top Speed40 MPH (64 KPH)
AccelerationExcellent! Just try to keep that front wheel down!
Range25 Miles (40 Kilometers)
With pedaling.
Watt Hours/Mile30 Wh/Mile
Curb Weight65 Pounds (29 Kilograms)
Tires24" Maxxix Hookworm

code by jerry