Twin Engine turning

[nf22]

I bought my 2019 242 Limited S last year and drove it all summer. This was my first jet boat, and first jet boat I ever drove, so going from a 19ft Stern Drive for 30 years that runs 70 MPH to a 24ft jet boat was a bit of a change. Overall, I love the boat, but I took it very easy on the boat last year & didn't push it or myself, being that it was new, I always had one of my kids on with me & I didn't have anyone to really guide me, unlike all of the experiance I gained driving/watching/learning on the IO's.

My question is geared toward the turning radius of the boat, particulaly with twin engines and making sharper turns at higher speeds. I guess I would not be asking the question if it was June or July but rather experiment myself, but since it is still winter, I thought I would ask.

When pulling tubers the whip that I could give them behind me from right to left was night and day between the IO and I mean that is in a good way for the jetboat. However, I found a couple of times when I would try and turn the boat at the end of the lake to go back the other way, that I was unsure I would make the complete turn without running into the beach. (obvioulsy, I slowed down and completed the turn etc), but regarding the twin engines, isn't there a methed to using the port throttle & stern throttle in conjunction with turning the steering wheel to make the turn sharper at say 20-30 MPH?

Any suggestions are greatly appreciated.

 

[Beachbummer]

Practice away from shore... I have found that accelerating makes the turn sharper. Best of luck!

 

[nf22]

Ha. It’s all about practice / trial and error, but with my kids never wanting to give me a break and having the new boat syndrome, I never got the chance to tune her up. Hopefully this summer I’m not so gun shy with her.

 

[Cobra Jet Steering LLC]

My steering system takes care of that and a lot more even turning without thrust add the Cobra super magnum ak-19 system and it will make you think you just purchased a different boat. the new boats are really bad at high speed bleed off due to the keel down the center of the boat and the rack and pinion steering being twice the travel of the regular steering helm. It also deals with better slow speed handling https://jetboaters.net/threads/basic-information-about-the-options-from-cobra-jet-steering-llc.16857/ soon to have an optional top inner fin for even more slow speed handling and optional extended fin bracket for quicker planing like my viper does for the 19 foot boats.

here is another video making an S turn off power both are courtesy of @swatski

 

[ifly4fun]

Put the hammer down and crank it.. I took mine out solo at the end the season and drove it like a jet ski. I was amazed and sharp it turn and had a blast doing it.

 

[Cobra Jet Steering LLC]

Put the hammer down and crank it.. I took mine out solo at the end the season and drove it like a jet ski. I was amazed and sharp it turn and had a blast doing it.

Your boat does not have the same hull or the articulating keel like his. Apples and Oranges

 

[ifly4fun]

Your boat does not have the same hull or the articulating keel like his. Apples and Oranges

I agree. I was only suggesting to go out solo and have some fun, see what it can do.

 

[Dough]

Wait, you didnt roll into a turn, then full reverse the inside engine as soon as you could? I thought everyone did that.

 

[ifly4fun]

Wait, you didnt roll into a turn, then full reverse the inside engine as soon as you could? I thought everyone did that.

I like the way you think - i need to try that next time.

 

[Ronnie]

I had a 23’ and have a 24’ twin engine Yamaha jet boat without keel or rudder and always found that they turn sharper in one direction (right I think) v. the other (left) and that this is most noticeable at high speeds. This is so consistent that my regular crew and tube riders know which side of a tube to be on if they want to have an easier ride. My understanding is that this happens because both Impellers rotate in the same direction. Cobra fins help, I doubt thrust vectors would because they are out of the water once the boat is on plane, but they don’t eliminate the problem.

One way to turn left a little sharper is to slow down a little before you start the turn, to let the bow dig into the water a little more and accelerate coming out of the turn, just like you would on the road.

 

[grywlfbg]

+1 to Ronnie's tip of slowing a bit, initiating the turn, then throttling up. Also a +1 for the Cobra fins. They will give you a lot more bite into the water when on plane.

 

[Dean P]

This thread is enlightening. I had no idea the Yamaha twins cause issues with steering. I thought all jets were common once on plane. Is it the rudder thing? Is that preventing the stern to swinging into a tight turn?

I am scared sh!t to spin mine out. I have tried but feel I'm about to be thrown overboard. I brace myself and all but, just, can't, do it. I can literally toss everyone out. Why is mine so different???

 

[Ronnie]

I had two single engine jet boats before the Yamahas, they all turned sharper in one direction than the other. I think it has more to do with the torque created by the impellers than whether the boat has a single or twin engines. I’m not an engineer, these are just observations I’ve made over the years.

None of my boats had or have keels or rudders, I could only spin or slide the lighter ones. Kinda of like its easy to spin or slide a lighter pwc than a heavier one.

 

[nf22]

Ronnie, thanks for the advice, when I have slowed down, it has worked, but rather when I was going 25-35 and making a shorter radius turn, rather than the wide looper that I saw the problem coming. Thank you as well Cobra, I am internally debating about fins.

 

[Matt Phillips]

pulling tubers is a constant use of the throttle. if ya want to whip them about a bit, slow down a bit before the turn, crank the wheel and punch it....they'll shoot around fast enough.

This one kind go says it all (note the direction of the tube wake is sideways)...

 

[seanmclean]

One way to turn left a little sharper is to slow down a little before you start the turn, to let the bow dig into the water a little more and accelerate coming out of the turn, just like you would on the road.

Yeah, this is the ticket. Back off the throttle a hair, turn, and then accelerate. Whip a tube like no one's business, magic fins not required.

 

[nf22]

I have been pulling tubers for 30 years, like I mentioned previously, the jet boat is night and day between a stern drive.. no need to use the throttle to whip back and forth in my boat, just short hard lefts and hard rights at 25-35mph and my 3 person tube whips the hell out of people over the wakes & the steering wheel snaps right back to position.. The jet boat actually performed so well that it literally snapped a bungee rope that I used for a few years with my stern drive.

I appreciate the advice, just looking to see if I’m missing something with the duel throttle at higher speeds...

 

[Ronnie]

My question is geared toward the turning radius ... regarding the twin engines, isn't there a methed to using the port throttle & stern throttle in conjunction with turning the steering wheel to make the turn sharper at say 20-30 MPH?

Any suggestions are greatly appreciated.

I think the method you referred to calls for the throttle of the inside engine in a turn to be reduced as the turn starts and brought back to wot at the end of the turn. How quickly the boat hooks / turns and how long it takes to get the speed back depends on how much the inside throttle is reduced .

This method works for making a quick turn but I only do it at the end of a run because you bleed off a lot of speed doing it and it seems to take forever to get back up to speed.The bonus of this move for me is that me and my boat are often stationary (well bobbing in its own wake) as the tube and tubers come around the side of the boat at high speed, sometimes just in time to hit the wake. As the primary driver when tubing it’s rare for me to enjoy the tubing from a guest’s / non-driver’s perspective, sometimes I have enough time to grab my phone and take a pic of the action instead of relying on someone else to get the shot.

 

[biffdotorg]

Wait, you didnt roll into a turn, then full reverse the inside engine as soon as you could? I thought everyone did that.

Sure, drive it like a Bobcat Skid Steer. Too funny. Next suggestion, get it up to 40-45mph, and throw it into hard reverse, and let us know what your first sub-move looks like. Be sure your guests (if any) are holding and Oh-$#%& Bar!

 

[Jameson Clark]

I went from years with multiple stern drives then went and got my Yamaha. I had the same feelings as you of not being able to turn as sharp on plane.

I am not trying to sales pitch you anymore, but the Cobra fins really do make a huge improvement in this area. I did my personal review of these fins back in 2018 here: https://jetboaters.net/threads/my-personal-views-review-of-the-cobra-venom-magnum-ak-with-mega-fangs.19526/

My #1 concern was what we are talking about today and here were my thoughts back then:

1. This was my biggest priority as the poor turning performance of this boat had already almost gotten me in a bad spot once and thankfully this was one of the most improved areas! I had read reviews saying how well these boats turn with the Cobra systems but I was skeptical... It absolutely 100% solved my complaint of this boat! It turns as sharp, or sharper, than my last I/O and also now bleeds off less speed in normal watersports steering and maneuvers. The boat feels like it really digs into a turn now and it is exactly what I was looking for. (100% improvement for me)