This thing is a piece of cheap plastic shroud, (yes, its genuine), on a .50 cent fan. When I look at the pictures and all the nice ergonomics, I thought it was aluminum, but no, complete garbage. Its just marketing, presentation, w the word Castle all over. No different than buying a knock off from Aliexpress.
Sending it back to seller, might as well custom make one w the X-Maxx aluminum fan, that is something that will work.
Or simply customize a 540 aluminum shroud and fan to make it fit. What amazes me is how others have not commented about it. Plan B is to make a heat sink with wrapped around copper (coil over the motor) and stage a crown w a fan.
I have seen custom applications for two stroke small bikes (where space is limited), and over powered engines, w coil copper in the cylinder head and a electric fan attached to it, something similar.