docnjoj
1 GW
Not relevent to KMX but to going downhill fast. Check out the video of a team Steintrike going down a luge chute in the summer. Supposedly 100km/hr speeds. Yes it is full suspension and is is about 4500 USD but it comes fully developed. Frames are a lot less, like mine.
http://www.steintrikes.com/gallery/movie_gallery/movie_gallery.php
otherDoc
http://www.steintrikes.com/gallery/movie_gallery/movie_gallery.php
otherDoc