A direct bolt on to your existing JCRACING SXR1500 Rear/Mid Sponsons. These are called our “race” blades because they can mount in any position front to back and stay within the bond flange legal limits which is race legal. We also removed the step in the first generation rear blade to add more surface area for more aggressive grip. These blades are not for everyone. If you cruise on the lake or river, we would suggest our first generation blades. If you race closed course and find yourself looking for more aggressive rear grip than our first generation blades have, give these a try.
As for placement, even with these race blades, we suggest starting at one or 2 holes forward from the rear then go from there. Some riders like it all the way back. That will make it turn a bit wider, but it will increase rear grip. Going further forward, the rear blade will act more like a mid sponson and it will turn tighter, changing the pivot point of the ski more towards the center of the boat. In both cases, you will need to adjust your body positioning to compensate and get the most from the move. All the way back, you will ride it with a longer handlepole (if you have an adjustable pole) and be hanging more off the back. As you move it forward, you will change your body positioning to ride it more over the bars. Try it and see what you think. 99% of this is personal preference which varies. That’s why we made them adjustable.