Been advised to fit trim tabs

Chris1956

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Mar 25, 2004
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Re: Been advised to fit trim tabs

That looks to be a high performance hull. What is length, brand and HP of the motor? What kind of prop and what is it's pitch?

Most small high performance boats do not need trim tabs, nor extensions of the antiventilation plate. They can easily rob speed and performance. I recommend you get rid to that whale tail.
 

H20Rat

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Mar 8, 2009
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Re: Been advised to fit trim tabs

wait, you can just walk in here and post pictures of that thing without a little detail! Looks like fun!!! I've seen old versions of that type of boat, basically a precursor to a modern PWC, but that thing is both a little larger than that, and new...

Anyway, I don't know if I'd put tabs on that... It looks like it handles fairly well already, I'm assuming the engine has trim? And as the previous post mentioned, get rid of the tail and try it again... Worst case, relocate your battery to the front.

Finally, even if you did want to put tabs, not going to happen on that hull... The angled part is too angled, and the part that is vertical is too close to the motor, it would hit the tabs when you turned.
 

oops!

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Oct 18, 2007
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Re: Been advised to fit trim tabs

um.....it could be just me....but the transom looks as if it is at the wrong angle. it should be around 110 deg. and it looks about 80.

that is why the need for tabs.

place them at the outward edge of the tow hooks. you will need to contact bennet with pics of the hull design. for them to suggest what kind of pistons.

smart tabs might work.....but again...piston length is key
 

Richardsix

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Oct 1, 2011
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Re: Been advised to fit trim tabs

Sorry, didnt mean to offend with lack of detail.
The hull is just under four metres, it is running a 2006 Evinrude etec 50hp
The prop is Alu 13.25/17.
I use the boat mainly for towing, I have not owned it long and feel it is slow to plane, once up...by god does it go!
With the current prop it will tow a kneeboard well, but will refuse to tow a ringo. I would rather have pulling power than top speed.
 

Mi duckdown

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Apr 14, 2007
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Re: Been advised to fit trim tabs

Take off that whale tail first, then try again. That motor has trim?
 

joewithaboat

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Jul 3, 2011
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Re: Been advised to fit trim tabs

Hello there. I put smart tabs SX on my boat earlier this year. I had an unusual install because i have a transom that is contoured in two directions that left little room for them. I'm almost positive you don't have enough room for them. Which is too bad they work great.
good luck!
 

Richardsix

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Oct 1, 2011
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Re: Been advised to fit trim tabs

It was made by a company called H2 Lifestyle and sold under the name of H2-Zippa. From what I can make out production of them stopped in around 2006, mine is one of the last made I think.
 

Bondo

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Re: Been advised to fit trim tabs

Sorry, didnt mean to offend with lack of detail.
The hull is just under four metres, it is running a 2006 Evinrude etec 50hp
The prop is Alu 13.25/17.
I use the boat mainly for towing, I have not owned it long and feel it is slow to plane, once up...by god does it go!
With the current prop it will tow a kneeboard well, but will refuse to tow a ringo. I would rather have pulling power than top speed.

Ayuh,... I'd say ya got the Wrong hull, for the Wrong application....
 

Philster

Captain
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Sep 15, 2009
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3,344
Re: Been advised to fit trim tabs

Bond-o, you can tow tubes and skiers with just about anything that planes.

If he can't tow a tube w/ rider, he just needs a little more power, not another hull.
 

John_S

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Jun 21, 2004
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Re: Been advised to fit trim tabs

This is not my boat, but still running same set up as mine, would give you a better idea of performance.
http://www.youtube.com/watch?v=YYOJhmvU_ts

Looks to be a larger motor than yours. Good person to talk to to see where he has motor height set to. ie how far above the bottom of the hull is he running the cav plate?

What is your current wot rpms and gps speed?

Towing kneeboards and tubes? Going to a lower pitch prop will help, but given the type of boat (and current power), probably not going to be good at it. How does it handle now with a knee boarder cutting on turns?
 

NHGuy

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May 21, 2009
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Re: Been advised to fit trim tabs

If you have extra top speed and not enough hole shot go down to a 15" pitch propeller. That will reduce top speed but make it pull onto plane better.
I don't like whale tails either, but they are intended to manage handing deficiencies like low speed bow rise and porpoising. Whoever installed the tail must have had some reason. So try the lower pitch prop both with and without the tail.
If you have power trim use it. Trim all the way down & in for lift off, then bump it up once on plane to adjust bow attitude & get engine efficiency.
Whale tails can take away top speed, but if you have enough top speed maybe you can keep the tail on and benefit from it's other attributes.
Ringo... Ringo Star? Those drums must be hard to bring onto a plane!
 

Richardsix

Seaman Apprentice
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Oct 1, 2011
Messages
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Re: Been advised to fit trim tabs

The boat in the vid is also running a 50hp motor, just a different make to mine.
The boat handles fine with a kneeboard behind, should also have said it tows a wakeboard good as well.
As for the question of RPM at wot, I have only had the boat a short time and in this time the rev counter has been playing up, so I dont trust it, I plan to fit a new one in the spring when the boat will be used again, then once I know revs will be in a poition to change prop. ( A new rev counter in the UK is ?250.00).
 

Chris1956

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Mar 25, 2004
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28,124
Re: Been advised to fit trim tabs

The video shows the operator trimming up for optimum performance. That is how you should run it (for fun), when not towing someone. A smaller pitch prop will give better low end power and quicker planing. Trim up until she starts to bounce up/down on her own, and then trim down until it stops bouncing. That will be best performance.

BTW - knee boards take less power to tow then tubes. But you already knew this.

Bag the whale tail and the trim tabs. They are not what you want.
 
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