GTX-2 questions before build starts

[cudaben]

I bought a GTX-2 a couple of months back- getting more parts bought, getting ready for the winter build.

The bottom deck (WDK) was supposed to be set up for a Yamaha engine and Kawasaki pump. It is actually set up all Kawasaki. I don't run Kawasaki engines or have any. I have been working with Yamaha power plants.

The bottom deck is setup for a 650 or 750/800 Kawasaki pump- (No shoe glued in).

I don't want to run a 750 pump with just a stuffer and a big hub impeller. But I don't want to splurge on mag pump either. Since I have to buy everything- pump, impeller, reductions nozzle, stuffer does it make sense to go with the 144 Yamaha pump? Will I see a noticeable improvement going from Kawasaki 140 to a Yamaha 144 with all the same mods?

This is a freeride boat, that will see some surf, but most f*ing around with friends and boat wake chasing. NOT A RACE BOAT.

 

[Vumad]

@Twinturbostang is a good source for this information. The gtx2 is usually a top deck kit on a sxr bottom deck. It should be setup for a sxr driveline if such is the case unless it has been modified. @rhaas sells conversion kits to run yamaha components in kawi machines. Rhaas makes great parts and is a great guy.

 

[Vumad]

You need to buy all of the parts anyway so start with rhaas. Running all yamaha or all kawi will make tuning much easier because lots of people have specs for all kinds of set ups. A good example is the classic x2 guys. No one has the same setup. Everyone has different motors, with different pipes, with different carbs, etc, so something like pump tuning can be a hassle. My superjet however is limited spec, so llts of people have a stock motor with a head, stock carbs, pipe, etc so i know exactly what prop to buy.

 

[cudaben]

Im familiar with Rhaas.
Just wondering if it is worth it to convert to Yamaha pump vs the kawasaki.
The outside pic it what it looked like when George sent it to the original buyer.

You can see the rotisserie I built- almost done with it. just need to add wheels and attachment points.

 

[Krenn Power Sports]

I don't think it really would be possible to convert kawasaki deck to a yamaha pump with out totaly re-designing/glassing the bottom.

 

[Vumad]

I don't think it really would be possible to convert kawasaki deck to a yamaha pump with out totaly re-designing/glassing the bottom.

Rhaas sells complete kits to retrofit the gen 1 to hold a yamaha motor and pump. The kawi 650 and 750/800 pumps use the same bolt patterns for the pump and the same through hull bearing. I cant say for sure how his kits adapt to the sxr, but its just a matter of drive shaft differences. He has what it takes to convert engine mounts, pump mounts and through hull. he can also remachine shafts for length.

@rhaas

 

[Vumad]

Im familiar with Rhaas.
Just wondering if it is worth it to convert to Yamaha pump vs the kawasaki.
The outside pic it what it looked like when George sent it to the original buyer.

You can see the rotisserie I built- almost done with it. just need to add wheels and attachment points.

If you want a freeride setup and the money isnt an issue, id personally prefer an all yamaha setup.

 

[Krenn Power Sports]

I have yet to see any sxr converted to use a Yamaha pump... I guess it's possible if your pockets are deep enough... I'd be curious to see this conversion.

 

[Vumad]

I have yet to see any sxr converted to use a Yamaha pump... I guess it's possible if your pockets are deep enough... I'd be curious to see this conversion.

I have yet to see any sxr converted to use a Yamaha pump... I guess it's possible if your pockets are deep enough... I'd be curious to see this conversion.

Personally I think it's a waste of money. We've all wasted money on things so I like to talk about how to get it done rather than if it is worth it. Personally I wouldn't convert a sxr to a Yamaha twin non-pv for the same reason I wouldn't put a corvette motor in an army tank. I wouldn't build a gen2 for freeride either with all the lighter fixsteer Superjet options. X2 have a following however, and people like to build them just to have something called a x2.

 

[cudaben]

I have spoke to a few big names in the sport, and a few guys from this site. I have also spoken to someone who has done this conversion- except he used a triple.
The consensus was- just run a Kawasaki pump.

My pockets are not that deep, LOL. but that being said money really isn't the issue- unless it is wasted money- buying parts that do not work and having to replace them.
I am curious what it costs to have a drive shaft shortened. I already have one that is from a waverunner 3 and it sticks into the hull like 1 foot.

I have destroyed (3) c75 large hub Kawasaki 140mm props from something... My guess is the Rhaas 701 conversion mounts and plate put too much of an angle on something or transmit 2 much vibration through drive line???? I had 2 pumps bearings fail while riding within 1 season and had a 750 pump bearing shaft snap off flush with the impeller. This lead to thrashing 3 expensive props. The last one I just pulled out (650 pump style) I tossed the ski into my rotisserie and cut away the silicone, the pump and drive shaft with impeller slide in and out effortlessly with fantastic alignment. I spent a bunch of time shimming the motor hoping it would last. A big reason I am looking to go to the Yamaha pump is hoping to eliminate this. I am also swapping around motor mounts, going to maybe try some Yamaha stockers????

I never had this problem running a Kawasaki engine, just since converting to Yamaha power.

 

[cudaben]

Personally I think it's a waste of money. We've all wasted money on things so I like to talk about how to get it done rather than if it is worth it. Personally I wouldn't convert a sxr to a Yamaha twin non-pv for the same reason I wouldn't put a corvette motor in an army tank. I wouldn't build a gen2 for freeride either with all the lighter fixsteer Superjet options. X2 have a following however, and people like to build them just to have something called a x2.

I like riding an x2 far better than riding any standup or sitdown- but I have never cared for how the X2 handles. I have always done front fills, my own or bought the cap from others, I chop the skis, cut out the seat area, done this or that to change how they ride.... So I am hoping the gtx2 will get me closer to how I want a ski to ride.