Yes, you can. There are several steps involved. This is a large project and one you should carefully consider before doing. There are other methods than my own, but this method worked for my application.
My example comes from my X2 which is still being prototyped. It is back on the water and I have had no issues as of yet.
You will need...
- Complete through hull fitting
- 650 sx steering cable (in addition to the one you already have)
- A yamaha QSTS control bracket.
- Cables and controls to connect to the bracket. (I am using the complete Yamaha QSTS, but you can use different cables and a lever pull)
- X2 brass trim connector fitting (part that connects trim cable to the control rod)
- Threaded rod (I cut the head off a stainless steel bolt).
- 1/2" PVC tubing
- Misc tools and supplies (heat gun, 5200, fiberglass, epoxy, etc)
A few steps will be different than my build. I will try to customize my advice for your build.
Start by obtaining the through hull fittings. The X2 contains 4, but I only needed 2. I removed all 4 and clean them by soaking in Chem Dip. I do not know if you can buy these new. They are a mofo to get out of the hull. The SX only has 1, so you will need to find 1 more.
Next, cut out your tray to access the pump area. The image included is after I have already finished removing the old system and installing the new system. You will need to select the proper spot to drill the hole to install the second fitting. Use a heat gun to shape your PVC. The PVC is slightly larger than the fitting, so I used 5200 on the fitting and secured with a hose clamp. I allowed it to dry before final installation into the hull. I used a combination of 5200 and thickened epoxy.
This is a good time to refoam your ski, add foot holds, and upgrade your cooling system. I when to 3/8" thin walled 304 stainless tubing when I did this job, and I get some serious cooling flow now. There are 3 tubes, and one is flush to the hull in the back. I changed this out to a full sized tube so my X2 is now set up for true duel cooling with a fully functioning stock siphon bilge. The 3rd tube is not yet installed in this picture. The SX will be much easier to work on. The X2 is very tight and it was extremely hard to prep and reinstall cleanly.
Here is the inside of the hull. The tubes have been cut shorten and the area was prepped before securing the tubes. This picture was taken during mock up. This is not final assembly but you get the idea. It should look the same as the steering tube.
You have probably realized these are not in order... Here is a picture of the mock up of the back end. You can see where the trim and steering controls come out of the hull. These controls are in the exact same place as the stock X2 controls. The SX will probably accomidate a very similar design. Steering on top, trim on the bottom. (note, the hull is upside down, so the cables are reversed, trim on top in this picture)
Here is the picture of the mock up of my steering. The 650sx cable lines up perfect with the X2 trim. However, the SX cable is too short for the X2 steering. I hear you can use a SXR cable for more throw, but I think you still have to extend it. The top is my steering. The piece of brass is the X2 trim connector from under the steering. It is connected to the ball joint piece by the thread rod (cut down bolt) i was speaking of.
Lastly is the mechanism behind the trim system. There are a lot of options in this category. For me, I maintained the complete system. These parts are actually from a wave raider. The cables are shorter on the raider than the GP1200. I have not done this job on a SX before so you need to think about the cables you need. I think your best bet may be to use a X2 trim cable, and GP1200 trim cables. There are many options. On my X2, at least for now, I have Yamaha QSTS for both up and down trim. For you 650sx, you will probably want your trim on a lever pull. To do this you need a lever and a different cable from the lever to the mechanism. You're going to have to figure this out on your own. In any case, the Yamaha QSTS bracket works very well. If you use a lever, simply connect your cable to one side, and put a spring on the other side.
EDIT: 1/2" PVC tubing.
