I bought the UFO fender on Amazon ( http://www.amazon.com/gp/product/B000GTYRH2/ref=oh_details_o05_s00_i00 ) which came with an incandescent light which used 21W and wasn't all that bright. I had purchased hand guards, signals, switches from highwaydirtbikes and figured I'd upgrade the tail/stop light as well.

According to my calculations(haven't measured it yet,) this circuit uses about 2W for the tail light and 3W for the stop light. The tail light has 28 wide angle red LED's (4x7 array) and the stop light is 21 white LED's (3x7). The white LED's(which have a higher Vf) shine through the outer portion of the lens which is red, the reds are in the center (an extra white thrown in there for a tag light.)