Twin Engine Steering Hardware and Fins

[captras]

Opinions regarding adding the second steering tie rod to the new Yamaha twins with the articulating keel. Is it really needed, or is it one more thing to spend money on? If it is necessary, why is it not standard from the factory? Can you just buy the tie rod....used to be available on CJ web page, but cant find it anymore? Lastly, if you were to install the TV, does Jetboat Pilot make a set of twin TV with a notch for the additional tie rod on the right nozzle?

 

[Tobes]

Is the additional tie rod NEEDED? No. Does it reduce play in the steering? Yes, as well as reduces wear (not so much reduces, just evenly distributes the pressure applied to the jet nozzle between both of them).

And by TV I am assuming you mean Thrust Vector fins? Those are made by a different company and utilize 2 fins per nozzle on a dual engine boat. Cobra Fins utilize 1 fin per nozzle. I am not sure if the TV allow for second tie rod or how it is designed so I cannot say if it will work or not (I am sure someone can chiime in on that).

Why didnt Yamaha install these things if they arent needed? The same reason every car manufacturer does not do things. Cost. While the cost may be a minimal thing to us, it affects their bottom line. They can get away with 1 tie rod for the proper operation so they do. You can always improve upon a design which is essentially why CJ sells these.

 

[Neutron]

An added benefit is if you break one steering cable you still have control of both nozzles

 

[captras]

Is the additional tie rod NEEDED? No. Does it reduce play in the steering? Yes, as well as reduces wear (not so much reduces, just evenly distributes the pressure applied to the jet nozzle between both of them).

And by TV I am assuming you mean Thrust Vector fins? Those are made by a different company and utilize 2 fins per nozzle on a dual engine boat. Cobra Fins utilize 1 fin per nozzle. I am not sure if the TV allow for second tie rod or how it is designed so I cannot say if it will work or not (I am sure someone can chiime in on that).

Why didnt Yamaha install these things if they arent needed? The same reason every car manufacturer does not do things. Cost. While the cost may be a minimal thing to us, it affects their bottom line. They can get away with 1 tie rod for the proper operation so they do. You can always improve upon a design which is essentially why CJ sells these.

In looking at the TV vs the CJ, I did notice that the new CJ only have 2 fins? If 2 are all that is necessary, why did they have 4 initially? Is 4 better than 2? Seems to me that the more surface area, the greater affect on the steering, so I would think 4 would give you more control?

 

[Neutron]

I would think it is because of the articulating keel already gives added steering input. 4 fins would be overkill. That would be 5 turning surfaces total

 

[Ronnie]

I think its because the tie rod is in the way and you can't just notch the fin since it is adjustable / moves up and down. Jeff @Cobra Jet Steering LLC may see this share his thoughts.

 

[Cobra Jet Steering LLC]

I started building this magnum A K system when the first twin engine boats with the rudder came out.
I addressed the particular needs of the factory system, remember the fins work all the time just like the keel the steering input is constant and the fangs add even more benefits to the system.
There is no need for more steering input especially with the V configuration and fixed fin setup, the A K system is very balanced and it also balances the work load of the entire system to both nozzles and both cables and with the fangs it actually reduces the work load.
Once you add this system to your boat you will want for nothing in the way of steering and handling of the boat.
This is not part time steering this steering is working if the boat is moving regardless of the speed And it is not expensive plus it is guaranteed with a 30 day money back guarantee so it just makes sense to try it .
15 years of experience ,3 large us patents and another pending it's what I do and plenty of people have this system on their boats it has been out for a couple years now .
I use 4 fins on non rudder/ keel equipped boats but this one has a rudder so it just needs some help.
Especially at speed since the huge keel down the center of the boat resists turning even the rudder has a hard time making the boat respond quickly.

 

[Cobra Jet Steering LLC]

By the way the current factory design has a lot to do with the existing patents and what is available and what has already been patented, also my tie rod is actually a heavy duty stainless one even the ends are stainless not aluminum like the original ones , the ends are rated for 2000 pound work load and since they are stainless they will last for a very long time.

Also to answer this question .
"does Jetboat Pilot make a set of twin TV with a notch for the additional tie rod on the right nozzle?"
As I see it other steering for the tie rod steering only has 3 part time fins and a plastic hook that really can't count as a fin, so cutting another one would reduce it to two plastic part time fins and two hooks , so you would be getting even less influence and only at slow speed, no high speed and no fangs for reverse and power steering.

 

[swatski]

Especially at speed since the huge keel down the center of the boat resists turning even the rudder has a hard time making the boat respond quickly.

Especially in E-series as their reverse is severely limited/non existent at speed.

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