Are there any cons to running steering assist fins?

[yall_mahaw]

First and foremost, I am not wanting to start a discussion comparing the two widely used products. There are plenty of threads, and even more opinions, for that. What I am curious about, is whether or not there are any real drawbacks to using either system? Do they cause a loss of top end speed? Do they increase the forces on the steering system, perhaps requiring additional maintenance than what Yamaha suggest? Is there an appreciable degradation of fuel economy? I would be curious to hear if people have taken them off after trying them out, either because they didn't feel that they were worth it or because of a related issue.

I fully understand that these are simple devices that are influencing the flow of water that is flowing from both the jets as well as the boat passing through it and are not a radical re-engineering of the steering system. Most of my experience is with cars, and there is always a trade off when making changes. For example - lower a car for handling, potentially ruin the geometry of your roll center or going the other way - put oversized tires on a 4x4 for ground clearance and potentially have rubbing issues, increased fuel consumption, and speedometer errors. There are always tradeoffs... but most are not showstoppers.

So maybe I am just over thinking this (it happens....) but would really like to tap into the knowledge of the forum and hear what you folks have to say.

 

[biffdotorg]

Other than rare occasions, or fabricated fodder, no. We would have heard if there was a common failure due to over stressing the pumps or steering system by now. They have been around for far too many years. If there had been, it would have probably lead to law suits etc.

You opened yourself up to a ton of opinions, so take them with a grain, I will start popping the corn.

 

[TX_Mercenary]

I’m also getting my popcorn ready…. Lol

 

[HangOutdoors]

First and foremost, I am not wanting to start a discussion comparing the two widely used products. There are plenty of threads, and even more opinions, for that. What I am curious about, is whether or not there are any real drawbacks to using either system? Do they cause a loss of top end speed? Do they increase the forces on the steering system, perhaps requiring additional maintenance than what Yamaha suggest? Is there an appreciable degradation of fuel economy? I would be curious to hear if people have taken them off after trying them out, either because they didn't feel that they were worth it or because of a related issue.

I fully understand that these are simple devices that are influencing the flow of water that is flowing from both the jets as well as the boat passing through it and are not a radical re-engineering of the steering system. Most of my experience is with cars, and there is always a trade off when making changes. For example - lower a car for handling, potentially ruin the geometry of your roll center or going the other way - put oversized tires on a 4x4 for ground clearance and potentially have rubbing issues, increased fuel consumption, and speedometer errors. There are always tradeoffs... but most are not showstoppers.

So maybe I am just over thinking this (it happens....) but would really like to tap into the knowledge of the forum and hear what you folks have to say.

There is a noticeable difference with fins for steering, I have ran my boat without and with. I have the Cobra's on mine, the Super Ultimate Magnum Series. I did not see any speed decrease and my gas mileage runs in the zone with what I should be getting. I have not seen nor thought of one drawback with them on, just benefits. Nothing has ever got hung up on them either and they are higher the my Keel Rudder so I have not hit them on anything. As far as in the way while swimming and boarding the boat, never had an issue with them and you would have to try pretty hard to hit your foot on them.

I don't have any info on the Thrust Vectors since I have never installed them.

While inspecting my pumps and the linkage I have seen no additional wear, or slop or anything else that could be attributable to the addition of fins. I have had mine on for two seasons and I tow tubes and riders 6 hours -8 hours a day when we are out and I am definitely working the steering back and forth hard. The kit I bought also had an additional Tie Rod so now I have two, one on each side. Never really liked or knew why Yamaha only put one on. At least on my model of boat, not sure about all the others.

My choice initially was based on the fact that I felt I wanted enhanced steering at slow no wake speeds as well as all speeds through full throttle, and more control if I have to deaccelerate fast in an emergency and turn the boat.

Hope the info helps.

 

[Gravy Jones]

Also curious about steering effort with fins down while at speed/on plane. Specifically CJ’s down full time and no fangs. Is the effort higher when turning (think tubing speed/turns)?

 

[TX_Mercenary]

i would also add that i dont like how the thrust vectors make the surf wake worse in conjuction with my twin engine and integrated wakebooster. its not an issue if you dont use a wakebooster or have a single engine

 

[HangOutdoors]

Also curious about steering effort with fins down while at speed/on plane. Specifically CJ’s down full time and no fangs. Is the effort higher when turning (think tubing speed/turns)?

It is a bit higher. What is nice is when you turn sharp you can feel the boat grab and cut and turn crisply and quicker. I would equate it to not feeling the ass end so sloppy as with the stock setup. I like a lot of control and feel. I personally find it much easier to work the tubes especially the Super Mable 3 person. We tube between 15mph and 20 mph depending on the water and area.

The boat also tracks very straight.

We run a lot of channels and small rivers around Lake St. Clair in and around the flats getting from place to place. What is nice is I can cut over hard and quicker when some ass hat is comes flying out of no where around reeds.

I don't have my fins set all the way down. I am using the third hole. I have played with them up and down and where I have them set gives me the feel and control I want. Some may want more or less at speed, what is good is you can adjust them for your preferred taste.

Ran out to grab a picture for you.

 

[Gravy Jones]

Which CJ’s are you running? No fangs?

 

[HangOutdoors]

Super Magnum AK-19 Deluxe, with no fangs.

 

[TX_Mercenary]

do you like those trim tabs? what do you usually use them for?

 

[HangOutdoors]

Trim tabs are like night and day on the chop. I guess it all depends on how you use your boat and what type of water you boat on and how rough it gets. On smaller in land lakes I don't even deploy them, although I can create a neat little wake while tubing with one further down.

On the Great Lakes and Lake St. Clair where we can be running 5-20 miles in 1-3 footers, it is a completely different ride. Much smoother, drastically reduces porpoising and the Admiral is noticeably happier. Turns a rough ride into a much better ride.

If I switch out or upgrade the boat, Tabs and Steering Fins and a Chartplotter will be bought right away.

 

[drewkaree]

Adding steering fins to my boat was a terrible idea, and I wish I had never done it. Now, I no longer have a reason for when something goes wrong other than captain's error. I wish I had never made this fateful decision, but I live with the problem as best as I can. I have had less opportunities to do fiberglass work from hitting docks, I have missed the opportunities to work on my marriage since I argue less with my wife about controlling the boat, and I seem to find myself focusing less on the problems with my steering than with other things on my boat - that one might be a wash.

 

[Mesa50]

I really haven’t felt the need for fins. The E series and D series boats have such effortless throttle levers, it’s easy to just bump in and out of forward to make small steering adjustments. I probably use the throttle levers a lot more than someone with fins when docking though. The only time I feel like fins would be beneficial, is when I’m on plane with a crosswind, and slight chop. This combination makes the tail wag, and feels weird when compared to my old Sea Ray. The Cobra Fins seem like they would help prevent the tail wagging feeling. The 2 times last year that I had a strong enough crosswind to feel the wagging, probably doesn’t justify the fins. However, there have been several people on this website, who have mentioned that their spouses went from not being comfortable driving, to enjoying getting behind the wheel once the fins were installed.

 

[RobbieO]

Adding steering fins to my boat was a terrible idea, and I wish I had never done it. Now, I no longer have a reason for when something goes wrong other than captain's error. I wish I had never made this fateful decision, but I live with the problem as best as I can. I have had less opportunities to do fiberglass work from hitting docks, I have missed the opportunities to work on my marriage since I argue less with my wife about controlling the boat, and I seem to find myself focusing less on the problems with my steering than with other things on my boat - that one might be a wash.

And you don't get to crash into the gas dock anymore...

 

[84rzv500r]

5 years with old style cobra jets here full down all the time (still spring loaded if you hit anything they swing outta the way) boat goes where you steer it on or off the throttle... no downside.. plus the trim tab and its a whole different boat... literally jumps on plane with some down tab... gives you slow cruse speeds below 30... better ride in chop... no porpising above 50 mph..

 

[lazergeek]

I never had an issue with docking, I got the Cobra's because I wanted better steering going fast as my tracking in the ocean was all over the place before the Cobra in the swells. Now its dead straight no constant steering corrections.

 

[Ronnie]

If there is any down side to having cobra jet fins it’s that the boat won’t feel as sloppy / have the tail slide out at speed when the fins are down. If you still want this feel just adjust the fins upward or buy the thrust vectors instead.

my fins are down and in their lowest position all the time. It makes the steering heavy at speed but I like the feel and control. My wife has complained about how hard it is to steer but that just may be her excuse to chill instead of drive.

here are a few pics of my setup, I combined cobra fins with thrust diverters which is unique but in retrospect the fangs were more effective for improved reverse steering (a lot less expensive as well).

 

[lazergeek]

If you decide on Cobra's but want the painted look you can also paint them. I painted mine with Rustolium to match the buckets and Clear Coated them.

 

[84rzv500r]

my fins are down and in their lowest position all the time. It makes the steering heavy at speed but I like the feel and control. My has complained about how hard it is to steer but that just may be her excuse to chill instead of drive.

here are a few pics of my setup, I combined cobra fins with thrust diverters which is unique but in retrospect the fangs were more effective for improved reverse steering (a lot less expensive as well).

Agreed the, CJ's do make the steering a bit heavier at speed however, I too like the feel and the boat is arrow straight at speed. It will turn hard and fast with authority. Only issue I have is that when I'm in really skinny water I leave the gates in full forward... this keeps the reverse buckets from kicking up crap off the bottom, sucking up crap and making a mess... i usually get in 3' of water before I bringing the power up off idle...

 

[Txbred]

Super Magnum AK-19 Deluxe, with no fangs.

Mine pulls to the right. I know Jeff says to put a little bit of a toe in the keel for tracking but I was running out of threads on the sterring rod.