Honda Senior had a son, Hirotoshi. And that started a company (je) Mugen, where the stuff was made for Honda's. But because Japanese apples are not far from trees.
So Hirotoshi Honda and his companion thought that they could also build a complete engine. And why would you not implement such an idea in a big and compelling way? Are we talking about the mid-seventies and the big source of inspiration? The Vincent HRD.
The four-tailed car was beautiful down to the last detail ....
One is made of it. That was already expensive enough.
The prototype still exists