Vumad
Super Hero, with a cape!
- Location
- St. Pete, FL
I race a lot with SXRs at the lake. I bought my SJ for freeride, but until my X2 is done (very soon I hope) and dialed in, the only thing I have to race is my SJ. I know the SXR is a better platform. I came very close to selling my SJ for a SXR, but after Daytona this year, I know that keeping the SJ was the right decision. It will be my freeride/surf boat, and my X2 will be my race boat.
1/13/13
I have been trying to keep up with the SXRs. That hull just smokes the SJ hull. They have me on both power and handling. I want to improve both, but I can't have any permanent handling changes for racing that alters my ability to surf ride. Everything has to be easily unbolted, like owning 2 ride plates for example.
The Dominator plate reduced my purposing and high speed stability, but I still have a lot of side-to-side roll and kick out of the rear end. I hope the destroyers will greatly improve the roll once I have them installed. However, they wont fix the kick out of the rear end when corning at high speeds.
I had never used rear sponsons before, but I had everything out working on my X2, so I figured I'd make an inexpensive test set real fast.
I used the plastic bag my glass came in since the resin doesn't stick to it. I cut some glass bigger than I needed so I could cut my shape out of the raw form. I used 1 layer of 24oz Weave sandwiched b/t 2 layers of 1208 Biax. I laid up my epoxy, then rolled the plastic keeping the soon-to-be part inside, I laid up the second sponson, then rolled the parts twice more, trapping the glass inside of the plastic. I placed 2 cinder blocks on top of this and let it sit to harden. (Both raw parts can be seen here, directly on top of each other. I cut them out while they were still slightly stuck so they are identical).
I then used a straight edge and a french curve to draw my shape. The overall sponsons is 14.5" x 1.25" measured by the area exposed under the bond rail. I cut it out using my 4" ginder and sanded the final shape with my DA.
The final part came out acceptable. They were rigid enough once bolted onto the ski. I used m4 bolts so they would fit into the stock bumper holes. I wish I would have made the part 1" longer so I didn't have to drill a hole in my rail, no biggy. They were pretty rigid once they were bolted on, but another layer of glass or some carbon would have taken the flex out completely. I also need to switch to some fender washers.
In the end, these things greatly improved my handling. I was able to take the corners much much harder than ever before (I don't slow down much for the corners anymore). The back end of the ski maintained traction in the corners with none of the kick-out that I usually experienced. They also greatly improved my set up for the corner. Previously, when I would enter the corner and let off the throttle... "prop breaking" (I think I made that phrase up), the back end of the ski would get really loose and sway, so I would ease off the throttle sooner making the braking more gradual. However, the sponsons completely removed this sway. I can now let off the throttle later, get more forward, and be more aggressive with my setup, w/o losing traction entering the corners.
I plan to later make a set out of 1/4" aluminum, and tap the bolt holes so I can very quickly add/remove them.
I still can't keep up with the SXRs. I get too much roll in the chop, and they are putting out more power than I am. I think once I have my destroyers on, it could be a pretty good race. Once I have my pole shortened and my motor mods bolted on, I think it could get pretty interesting and competitive.
1/13/13
I have been trying to keep up with the SXRs. That hull just smokes the SJ hull. They have me on both power and handling. I want to improve both, but I can't have any permanent handling changes for racing that alters my ability to surf ride. Everything has to be easily unbolted, like owning 2 ride plates for example.
The Dominator plate reduced my purposing and high speed stability, but I still have a lot of side-to-side roll and kick out of the rear end. I hope the destroyers will greatly improve the roll once I have them installed. However, they wont fix the kick out of the rear end when corning at high speeds.
I had never used rear sponsons before, but I had everything out working on my X2, so I figured I'd make an inexpensive test set real fast.
I used the plastic bag my glass came in since the resin doesn't stick to it. I cut some glass bigger than I needed so I could cut my shape out of the raw form. I used 1 layer of 24oz Weave sandwiched b/t 2 layers of 1208 Biax. I laid up my epoxy, then rolled the plastic keeping the soon-to-be part inside, I laid up the second sponson, then rolled the parts twice more, trapping the glass inside of the plastic. I placed 2 cinder blocks on top of this and let it sit to harden. (Both raw parts can be seen here, directly on top of each other. I cut them out while they were still slightly stuck so they are identical).
I then used a straight edge and a french curve to draw my shape. The overall sponsons is 14.5" x 1.25" measured by the area exposed under the bond rail. I cut it out using my 4" ginder and sanded the final shape with my DA.
The final part came out acceptable. They were rigid enough once bolted onto the ski. I used m4 bolts so they would fit into the stock bumper holes. I wish I would have made the part 1" longer so I didn't have to drill a hole in my rail, no biggy. They were pretty rigid once they were bolted on, but another layer of glass or some carbon would have taken the flex out completely. I also need to switch to some fender washers.
In the end, these things greatly improved my handling. I was able to take the corners much much harder than ever before (I don't slow down much for the corners anymore). The back end of the ski maintained traction in the corners with none of the kick-out that I usually experienced. They also greatly improved my set up for the corner. Previously, when I would enter the corner and let off the throttle... "prop breaking" (I think I made that phrase up), the back end of the ski would get really loose and sway, so I would ease off the throttle sooner making the braking more gradual. However, the sponsons completely removed this sway. I can now let off the throttle later, get more forward, and be more aggressive with my setup, w/o losing traction entering the corners.
I plan to later make a set out of 1/4" aluminum, and tap the bolt holes so I can very quickly add/remove them.
I still can't keep up with the SXRs. I get too much roll in the chop, and they are putting out more power than I am. I think once I have my destroyers on, it could be a pretty good race. Once I have my pole shortened and my motor mods bolted on, I think it could get pretty interesting and competitive.
