Electric Bikes - E-bike retrofit DIY - sources?

I normally thumb my nose at those lazy rider e-bike contraptions BUT I'm brainstorming a bike designed to haul 100+ pounds up significant grades and my legs will need a little help.

Anyone know of a good in hub motor that I could retrofit an existing bike with?
I can source a battery on my own so thats not a problem.






If anyone is interested in my plan, I'm going to be building a bike trailer fashioned with mounts to carry several other bikes. I will be making frequent trips to the county dump and recycling site collecting discarded bicycles so they can be refurbished and released back into the community as usable means of transportation

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In Scotland Ben Cooper at Kinetics Bicycles (http://www.kinetics.org.uk/) is knowledgeable about retrofit kits (http://www.kinetics.org.uk/html/heinzmann_kits.shtml) such as the Heinzmann (http://www.heinzmann.com/index.php?lang=en), and will answer questions.
There are still a few Giant Lites (http://www.electricvehiclesnw.com/main/lite.htm) available at Electric Bikes Northwest (http://www.electricvehiclesnw.com/index.htm). They have the motor inline to the chain which allows for more torque from a small motor. I have the Giant Lite and carried tons of stuff on it. It currently has an XtraCycle kit on it, and carries a lot of weight on a regular basis.

Thank you both for the links

Thanks especially for the link to that Endless-Sphere forum, seems like I could get some help there

The other links have some interesting stuff but damn are they expensive. Because this is for a not for profit organization, budget is a huge consideration. Anything out there a bit more DIY?

Here is a link to what you're looking for.
http://www.jstraubel.com/ebike/ebike.htm
http://www.jstraubel.com/ebike/Bikeside.jpg
This bike has an electric motor, which drives the wheel through a jackshaft made from bicycle hubs with multi speed cogs and derailleur selection.
http://www.jstraubel.com/ebike/IntShaft.jpg

dwoloz,

What grades are you expecting to encounter? My brushless, gearless Crystalyte will pull an 8% in excess of 20MPH while I'm pulling my 100lbs. of children and trailer. However, if I were pulling 100+lbs. up protracted climbs on a regular basis, I would get something geared down to keep the motor near it's highest efficiency in these tough situations. The Stokemonkey is the same hub motor that I use except it is geared down to apply heavy torque to the cranks; the cyclone works in a similar manner. Either of these would be better suited for your needs than a gearless hub motor. However, there are planetary geared hub motors such as this model which I am very interested in trying in an ATB application:
http://www.freeenergystore.com/New%20Pictures/Elec%20Car%20/1125hub.jpg

Freeenergystore.com is taking orders for this hub motor, but the wait is several months.