If Honda continued making big bores back in 73-74, this wouldn't be an issue, the honda was built for fun, its still air cool, and would be very interesting to know its performance.
I like odd ball hybrid, he built a nice bike, Hats off to the owner that made it happen. Nice Job, For pre 75 racing, well their has been plenty of illegal bikes been built here over the years of vintage racing, even in the 60`s and 70`s, but everybody excepted those bikes back then. Its all about having fun, not about the trophy.