Originally Posted by mswantak
I've been getting closer and closer to building one of those myself. I'm convinced I can make it better looking. The main thing that sticks a thumb in my eye is the gas tank. One from a small street bike that has a toptube tunnel would get the tank down where it belongs.
A rear-mounted fuel tank could be what you're looking for.
http://thatsdax.com/ENGINE_KIT_PARTS_PAGE_1.html
or this under top tube 1-gal tank.