Friends
I'm working on building a 2 person quad bike http://www.americanspeedster.com/side-kick.htm and am looking for advice on how to power it. Obviously this is not a speed machine, but it would be nice to have the ability to cruse at near 20mph on the flats, and will need a reasonable amount of torque to move the weight of two people plus our groceries in the back (350lbs?), especially up medium hills. The designer (and comments from others) have good things to say about the Crystalyte motors, but I was wondering about different geared or chain-driven options too, like geared hub motors, or the Cyclone system or something similar that will allow me to use my gearing too. Will there be much differences in the range of these options? Should I spend the bucks on a LiFePo4 battery? If I go with a hub motor, any comments on Crystalyte vs. Golden Motor or others?

In the end I'd like a minimum of 15-20 mile range, and then put a few solar panels on the top for a self-charging system.

Any comments would be appreciated!

Thanks
Wayne