u are all forgetting the point, who cares about MPH. best of the best are all the riders head to head.
there is race at every rally on every ride that lasts for miles and miles, all the fastest bikes get antsy then the second one guy guns past the ride leader and its on. Until I got a really fast bike I didn't realize how this worked. At any given rally there are only about 4-8 bikes in this group. we know who we are but 90% of everybody else at the rally has any clue.
Those are the riders i will always consider the fastest of the fast.
no need for sanctioned events, every rally proves who is the fastest, just take the fastest guys at each rally and there u go thats it.