Thanks to”small wheels”  (for the link in the comments thread of the FZ1 build) it seems that there’s a longer history of this than I realized.  As he said it’s “already (been) done in the ’80 by Jean Claude OLIVIER, french importater of Yamaha who even race it at the Paris-Dakar”

And here’s a shot of the 87 version.  Go check out the complete page.  It’s in original German Here… or the Google Translated version Here