Any experience with Trim Tabs on Scarab 195?

[Jacques]

I have been experience some porpoising in calm waters, usually fix it by lowering the speed or by turning a little, but I am wondering if the trim tabs would help.

I know these boats get on plan really fast, so there is much improvement to do on that matter, but I am more interested on improving how it performs and make it more enjoyable for everyone.

Have anyone installed them? Feedback? Ideas?

 

[dougewasiuk]

Same problem here. Was curious about that. The porpoising is annoying

 

[Jacques]

Since our boats don't have a flat transom, it's very difficult to fit the tabs. I have shared pictures and measurements with: Nauticus, LectroTab, Volvo (for the interceptors), Bennett, Lenco and Lewis Marine and unfortunately they didn't find a way to fit them despite all their efforts. I am just waiting for Bennett, but it does not look like we are going to have a different answer.

It will be matter to reduce speed or turn a little bit, or even play with the weight distribution if you have how.

I'll keep you updated if there is any change.

 

[John Carnevale]

Volvo penta TQ tabs (best and most readily available), hydrotabs or Humphree should work on your boat. I am looking at installing these on a 215 HOI, only issue is that the cooling plates are possibly in the way but I plan to make an "adapter." Also, Scarab has some tabs that supposedly eliminate the porposing problem but are not adjustable. I want adjustable tabs so I can drop the bow in chop.

All this said, it is terrible that Scarab would release a boat with this problem......I am not a happy camper with Scarab as not only do the boats porpoise like a dolphin, the hull design makes it impossible to use conventional trim tabs. I started another thread about the issue and I believe the Volvo TQ tabs are the best option based on helpful I put from others.....only ones that "might" fit.

 

[swatski]

We are working with Lectrotab on a new trim/tab kit for new 240 Yammies. Those guys are awesome to work with, and most responsive. Here is some of the discussion of the design (post #30):
https://jetboaters.net/threads/trim-tabs-options-wake-surfing-and-cruising.12031/page-2

Our tabs are in the final stages of design, we should have CAD files to post next week, but it is pretty simple -- 9x16 (chord x span, or width) -- largest we can fit and safely operate with a single actuator and max range.
An install like @paul075 here might work for you. Ours will be a bit different and tapered up, but this should give you a general idea:

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[John Carnevale]

Possibly would work on the scarab but the tabs would have to be mounted 1" above the bottom of the hull. The 215 scarab have aluminum cooling plates notched into the hull....basically exactly where the trim tabs need to mount. They would probably work but wouldn't provide as much lift if mount 1" higher than shown in photos? What are you're thoughts?

 

[swatski]

Possibly would work on the scarab but the tabs would have to be mounted 1" above the bottom of the hull. The 215 scarab have aluminum cooling plates notched into the hull....basically exactly where the trim tabs need to mount. They would probably work but wouldn't provide as much lift if mount 1" higher than shown in photos? What are you're thoughts?

Oh, we will be mounting at about .75" above the bottom of the hull, too. We could mount flush but the idea is to have as little (or NO) interference from the tabs when not needed/out of the water, or when submerged while surfing (on the surf side).

I think Volvo QL are a beautiful thing. But I think those are better suited for larger vessels. After looking into all of it way more/longer than I should have, my read on this (and some experience with my previous boats) is that with small vessels like ours any additional lift is a good thing in rough water. Adding traditional tabs/plates can feel almost like adding some length to the hull.

If considering Bennetts, are you talking to tabman on thehulltruth? He is fantastic.

I like the Lectrotabs as their electromechanical actuators are (I think) ahead of everyone else as far as the design quirks. They used to be a marine air conditioning (engineering) company that evolved into a major trim tabs builder that you never heard of. Their marketing is next to non-existent as they mostly make OEM stuff. But they have been great to work with, and @Bruce has sent numerous Yamaha owners to them who all got helped, so they know about this forum and are familiar with idiosyncrasies of our jet boats.
Here are their contacts. If you call the main number you will talk to Claibourne. Or email Dan dan@lectrotab.com

Dan Roberts
Linear Devices Corp
DBA Lectrotab and Sentry
11126 Air Park Road
Suite G
Ashland, VA 23005
Office: 804-368-8428
Mobile: 804-432-0513
Fax: 804-368-8438

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[John Carnevale]

Well, if you are mounting the tabs .75" above the bottom of the hull, not sure an extra .25" would be a dramatic reduction in lift? I can probably sneak them down to the .75" range depending on how the mounting tab and hinges are configured. So, are these tabs available yet? I did speak with Dan from Lectrotab but I got the impression that they are in early stages and likely won't be available for a year. I will be selling this boat or bringing to the scrap yard before then ....can't stand the boat due to porpoising.

Scarab should be ashamed for releasing/selling such a poorly designed boat and there solution is to add some lame permanent tab to increase lift......this surely will reduce an already poor fuel consumption rate and probably reduce top speed. Basically, they are trying to put lipstick on a pig and minimize customer complaints....frankly they should recall all the boats and STOP selling such a poorly designed boat! Until a real solution becomes available I will be voicing my opinion and hopefully prevent people from making the same 60k error I made!

 

[swatski]

Well, if you are mounting the tabs .75" above the bottom of the hull, not sure an extra .25" would be a dramatic reduction in lift? I can probably sneak them down to the .75" range depending on how the mounting tab and hinges are configured. So, are these tabs available yet? I did speak with Dan from Lectrotab but I got the impression that they are in early stages and likely won't be available for a year. I will be selling this boat or bringing to the scrap yard before then ....can't stand the boat due to porpoising.

Scarab should be ashamed for releasing/selling such a poorly designed boat and there solution is to add some lame permanent tab to increase lift......this surely will reduce an already poor fuel consumption rate and probably reduce top speed. Basically, they are trying to put lipstick on a pig and minimize customer complaints....frankly they should recall all the boats and STOP selling such a poorly designed boat! Until a real solution becomes available I will be voicing my opinion and hopefully prevent people from making the same 60k error I made!

I will be updating the thread on our custom tabs https://jetboaters.net/threads/trim-tabs-options-wake-surfing-and-cruising.12031/page-2 Those should be ready in about two weeks.
I believe Lactrotab could sell you a kit with standard tabs anytime, 12x12 or 9x12 would probably be the sizes you would be looking at. I have not had a chance to interrogate the Scarab transom much, so not sure what would be best. I would be interested in looking at some pics.
I think that well a set of designed and mounted tabs would make a HUGE difference in your boats' handling. Definitely worth looking into.

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[Skytour]

Russ Williams at Linear Devices now has a Lectrotab electromechanical trim tab system for the Scarab 195 that mounts nicely to the transom. They fabricated an upper bracket specifically for the 195.

 

[John Carnevale]

That is an interesting set up but I would consider the Volvo Penta interceptor tabs. I have them on my 215, they work great and aren’t visible. Also they have option for auto trim.

 

[Enduro900]

That is an interesting set up but I would consider the Volvo Penta interceptor tabs. I have them on my 215, they work great and aren’t visible. Also they have option for auto trim.

John, can you post some pictures of your trim set up and also an update on your Scarab handling???

I am considering Scarab 195, 215 or even a 255 next spring but it seems whether Scarab, Yamaha or Chaparral they all benefit from tabs.....

Thx

 

[John Carnevale]

John, can you post some pictures of your trim set up and also an update on your Scarab handling???

I am considering Scarab 195, 215 or even a 255 next spring but it seems whether Scarab, Yamaha or Chaparral they all benefit from tabs.....

Thx

Hello,

I posted quite a few p

John, can you post some pictures of your trim set up and also an update on your Scarab handling???

I am considering Scarab 195, 215 or even a 255 next spring but it seems whether Scarab, Yamaha or Chaparral they all benefit from tabs.....

Thx

 

[John Carnevale]

Hello,
Photos should be in the thread or perhaps on a separate thread. Let me know if not but I used the Volvo Penta tabs. I had photos of the Install, as well as, someone else who installed them on another 215 HOI. I will say they make the boat 100% more enjoyable and work flawlessly.

 

[Skytour]

John, can you post some pictures of your trim set up and also an update on your Scarab handling???

I am considering Scarab 195, 215 or even a 255 next spring but it seems whether Scarab, Yamaha or Chaparral they all benefit from tabs.....

Thx

The addition of tabs and thrust vector significantly improve handling and docking under a variety of sea conditions. Consider it essential equipment for a jet boat.

 

[Enduro900]

Hello,
Photos should be in the thread or perhaps on a separate thread. Let me know if not but I used the Volvo Penta tabs. I had photos of the Install, as well as, someone else who installed them on another 215 HOI. I will say they make the boat 100% more enjoyable and work flawlessly.

I just found your pictures on the scarab 285 thread thanks! This seems like the perfect solution for the Scarabs as is fits better/no actuator hanging off the swim platform/in the way like the other system/pictures.

Here is a link to the other thread:

https://jetboaters.net/threads/scarab-285.19669/page-2#post-402353

I see your control panel has an “A” on your control panel, is that for auto mode? Also, do you surf? I was wondering if you can use one side only to create a better wave....

Wow, it looks like the auto option is another $1100 and you have to adjust the tabs underway, then the auto takes over?

Have you noticed if it helps you plane faster with a boat load of people?

Sorry for all the questions......

 

[John Carnevale]

The short answer is YES to all of your questions!!

I did not install the auto feature but it might be worth it as I am constantly adjusting the tabs as people shift around on the boat and as water conditions change. The tabs do seem to have an impact on the surf wave as you can lift the opposite side of the boat and force the “surf corner” of the boat into the water. We still find ourselves losing up a corner with people or ballast as jet boats are very light so not great for surfing without ballast. Our kids are 10-12 and weigh under 100 pounds so they are able to surf and throw the rope (with ballast) but I am 200 pounds and just barely enough of a “push” for me to let go of the rope....still fun even getting pulled with the rope. Finally, with both tabs down, the boat virtually instantly is on plane, you can pull the heaviest of tuners, skiers etc with very little bow rise and a loaded boat.

These tabs prevented me from selling the boat...absolutely hated not being able to drop the bow in chop and my boat had an issue with porpoising...both problems solved.

If you can afford it and want to surf I would buy the HOI 215 or 255 with the twin 300hp (or a wake boar) and wake option. I have a 2015 215 HOI with twin 250HP and will be selling to upgrade to 255 if you have any interest!

 

[John Carnevale]

Sorry for all the typos ?

 

[Enduro900]

The short answer is YES to all of your questions!!

I did not install the auto feature but it might be worth it as I am constantly adjusting the tabs as people shift around on the boat and as water conditions change. The tabs do seem to have an impact on the surf wave as you can lift the opposite side of the boat and force the “surf corner” of the boat into the water. We still find ourselves losing up a corner with people or ballast as jet boats are very light so not great for surfing without ballast. Our kids are 10-12 and weigh under 100 pounds so they are able to surf and throw the rope (with ballast) but I am 200 pounds and just barely enough of a “push” for me to let go of the rope....still fun even getting pulled with the rope. Finally, with both tabs down, the boat virtually instantly is on plane, you can pull the heaviest of tuners, skiers etc with very little bow rise and a loaded boat.

These tabs prevented me from selling the boat...absolutely hated not being able to drop the bow in chop and my boat had an issue with porpoising...both problems solved.

If you can afford it and want to surf I would buy the HOI 215 or 255 with the twin 300hp (or a wake boar) and wake option. I have a 2015 215 HOI with twin 250HP and will be selling to upgrade to 255 if you have any interest!

Interesting....do the tabs drop the top speed much?

I see the concept from a “drag” standpoint, causing the lowering of the bow. Just wondering if this effects speed much. I do like how clean they are compared to normal tabs/plates.

Haha yes i May have interest in your boat!

Do you use manual ballast? It doesn’t look like you have the wake edition from the pics i saw...

Are you on Norris lake or in Tennessee? My daughter lives in Dayton and works in Chattanooga.

Can you pm me pics, specs and price?

Thx

 

[HoneybadgerFL]

I just wanted to take a minute to add to this I'm new to this forum (I have a scarab 165 HO) I'm going to post some pictures of what I believe would resolve the porpoising problem if not the next best solution that I was told Is possibly a nozzle wedge you can find them online I'll try to post the link to one company that sells them here and it varies in degrees from 2° to 8°, also I'm posting pictures for people that can change the trajectory of their jet on the back of their boat by flipping around this little piece so The piece where the bolt goes through seen in the pictures needs to be closest to the FRONT of the boat, thus helping face the jet down into the water, a little bit which might help with porphosing ???‍??‍, I'm only able to add the screenshot of the company that makes wedges for jet boats thus again when installed will turn the jet down to the bottom helping keep the nose down preventing porpoising.... I know it's really long but I hope that this helps! I've been looking for almost 2 years to try to resolve this situation. This is not my information I'm only passing it along to the masses I HOPE THIS HELPS ANYONE NEEDING SOME HELP!!