Hi everyone. I'm new here, but wanted to weigh in on my experience installing the Cobra Fins super magnum ak-19 deluxe system.
I just purchased a month ago a Yamaha 275 SE. I loved the layout, design and the fact it was a jet boat and safe for the kids to swim behind and do water sport activities. Being out of boating for about 15 years, I did have a decade of experience previously with I/O's and outboard motors and I quickly realized that the jet boat, while fast to plane good at handling while power was being applied, was very poor at low speeds and also while at speed when you cut power.
I came into this site seeing if others had any suggestions and quickly learned about the Cobra system, as well as the thrust vectors from another supplier. I did a bunch of research, read a ton of posts and decided to go with the Cobra system, especially after speaking to Jeff about his product.
While the thrust vectors seem like they would help at slow speeds, I didn't see how they would assist at speed when cutting power and trying to steer the boat quickly since they retract up when going fast. This is something I quickly realized could be a safety hazard if you need to stop and move quickly to avoid a collision.
At low speeds and when cutting power, my boat would just slide, almost like a car on ice would feel. You would have to try to steer it, but your inputs had little effect.
I spent a little over 2 hours installing the Cobra Fins, which arrived about 2 days after ordering them. They included good instructions, as well as I found some informative videos from other customers on YouTube. Today, April 2, I got a chance to finally get my boat launched and out onto the water.
All I can say is wow. I noticed within the first minute idling, that at low speed the boat responded immediately to my steering inputs. It felt like the boat handled like it should have from the factory. At speed the boat felt like it was on rails. It tracked straight and turned immediately on command. When cutting power, the boat actually was completely controllable. Wow, I was very impressed. What was even more impressive was in tight quarters with other boats, I wasn't sliding and praying the boat wouldn't hit them. I had total control in forward and reverse (I also purchased the fangs per Jeff's recommendation).
Bottom line fellow jet boaters is that Jeff's cobra fins work and work well. Low speed, at speed, cutting speed and parking in forward or reverse, they make a huge improvement. Yamaha should sign a licensing deal on Jeff's fins since he has multiple parents because they just work and make a good boat, a great handling boat.
I'm not affiliated, compensated or involved at all with Cobra fins or Jeff, but just an impressed customer who resolved a couple of major concerns I had with my boat the first month I had it.
If you want better low speed handling or find that you have difficulty handling your jet boat the Cobra fins are a very cost effective solution and Jeff is a wealth of information if you need help installing them or support.
I highly recommend them.