Hi All
After getting my rigger out for the first
Time gps at 90 km/hr not to bad.I am running
A hyper 21 onfa motor has anyone done any
Mods to this motor porting crank work
Or head button ?

If you're still using the stock heat-sink head you can remove most of the fins as you don't need them. You'll not only reduce weight, have less hanging out in the open air but will allow the engine to build up heat for better performance. With the engine so close to the cool air coming off the water it doesn't need those big heat-sinks.
Post some shots of your boat when you get a chance to.