Monday, March 22, 2010

Vic made me post this.....


Wow, the last post was feb 6th....
I've been too depressed. My dream car is up on blocks. In frustration, I gutted every electronic component to start over with modern electronics, batteries, and motors.
I had to research electric motors and find a manufacturer that could meet a few requirements.
1. Push 400 pounds up a 15% grade (that's 200 pounds of velo, and 200 pounds of lard). I live on a 15% grade, so the 15% part is important.
2. Allow for a reverse -- it's not like you can put your feet down and go backwards.
3. Cover 70 miles without a charge (this is more of a battery issue than a motor issue)
4. Not run through the body -- many motor solutions use the crank system to drive them. I plan to use an internally geared hub for shifting. They typically can't take much power, and the monocoque construction of the velo bends when I press with all my might -- bad news for powering through the drivetrain.
5. Sustain 20 MPH over the bulk of my ride.

I found out that when I was pedaling with the old motor system, I was actually fighting the motor when my power output was in excess of the speed that the motor could drive the velomobile.

The new motor will probably have the same problem, but if I am pedaling faster than the motor, what I need to do is cut the power and pedal on my own power.

After talking with everyone and their mother about how to power this thing (every ebay seller, every internet ebike seller, etc), I'm planning on getting a BMC motor from:
http://www.electric-bikes.com/betterbikes/bmc.html
Whenever I can save my pennies to pay for it. I'll get a large capacity LiFePO4 battery direct from China at a place that seems to have good reviews at endlesssphere.com. In the process, I will have to change the power side of the drivetrain -- I have parts coming for that which I will show in another post. Basically, in the middle of the velomobile there is a transfer case of sorts. I'm going to mount an internally geared hub in there and affix a cog to the disk brake side of the transfer hub, and the motor. The other alternative is to mount two hubs in the middle with a crossover chain, but I don't think it will fit.


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