All I was saying is this: A. In the US these cylinders and heads are difficult to find. Yes, they are far superior to the Banshee motor. However, how much would all this cost? I do not know. I was not saying that the guy should not do it. If he has the money, and the ability to fabricate the pipe spigot mount, then hell yeah, go for it. But if he is just looking for a trick and some power (top end) then just port the stock cylinders. Quite honestly, if a set of RZ cylinders, head, servos, and CDI fell in my lap today, it would be on my banshee tomorrow. End of story. Later.
eric

 

I'm with you. This sounds like a unique and effective mod. Like I say, I have some time before the next rebuild, so for now I shall research.
Thanks for the info. I am anxious to see the dyno results