HI Mad monster.
I also have the nova racing head and I do not think it's worth the money because it's not lowering the temps. So I bought a crazy nut head instead and that one works really well.
If you are running very hot you should check your carb setting. Mine are 3.5 turns out on the HSN and 0.5 -1 turn in from flush on the LSN . I have tried to use the setting CEN recommend but the engine keeps over heating.
With the setting I use I can still do wheelies and hit 3rd gear.