Tony Foale built a superbike girder. Best girder ever. A Hossack can look similar to a girder but is much different and more advanced. McCraken and others suspended the steering head, Hossack like, which I find intersting also. If anyone is fabricating chassis or suspension and they don't own a copy of Tony Foale's landmark book (I have a 1984 printing) The fabricator/designer isn't taking his craft seriously enough. Fun read for non engineering types too. Buy Tony's book and join the chassis list to be exposed to motorcycle brainiacs from around the world.
Tom Graham