I'm also about to make that plunge. I am aiming toward the Tonxin Mini Motor (also called the Nano Motor in England) with a 3.2 amp, 36v DeWalt LiPo battery.

The motor is 180 Watts, but has internal gearing and a freewheel that give it the torque of a 250 watt motor. Weight of the motor is 5 pounds and the battery is 2.5 pounds. Wiring and the controller should keep the total weight under 10 pounds.

I intend to use it on the front wheel of my recumbent where I can easily swap in in and out at will. As you can tell, this is not intended to be an electric motorcycle, just a boost up the small hills I encounter.

Some folks on a different forum reported problems with the company, but over the last several months that I have been watching it, the descriptions and product photos indicate that changes have been made in the motor.

Here is a link to the company (in China). If you take time to navigate, and you can learn a slightly skewed English, there is a lot of info.

http://www.tongxin.net.cn/tongxin1.jpg
http://www.tongxin.net.cn/tongxin2.jpg