Oh yeah... but those things are in museums and personal collections ... and are worth thousands and thousands of dolars... I actually know little about them... and my impression was this guy was asking about something he could 'buy and ride'.
My impression was he liked the idea of more performance... without having to jump through all the loopholes of it being a 'motorcycle.
In that case... (if he's got guts)... get something like a Zuma... faster than a ped... supposed to be licensed as a motorcycle... but looks like a Spree... (so most cops are unlikely to 'realize' its supposed to be fully licensed and insured).
If his state and local area isn't too Nazified... then he might get away with it forever.
(however... don't flaunt the traffic laws... don't vie with cars for position... always be in "stealth" mode)