I have been a Mazda fan, I had a built (racingbeat.com) and tricked out 72 RX2 (Yes, there is a such thing, lol). That is an interesting bike. Looks like it might be a two rotor and if so, interesting to see only one spark plug per cyl. Mazda used two spark plugs per rotor, one leading and one trailing. The trailing spark plug would kick in at a higher rpm to keep up with the speed of the rotor and burn all the fuel as I understand it, been a while, long while.
I miss my Mazda RX2.