View Full Version : Trim Tabs for Cyclone 540

04-12-2009, 04:43 PM
Gday folks,

I've had the Cyclone for a while now. Great little boat but with big twin battaries and a 90 Optimax hanging off the stern it's a bit tail heavy which leads to some annoying and constant porpoising.

Methinks it's time for some trim tabs, but which ones?

Looks like Bennett M80 or M120 might be suitable. Any ideas? Would this reliably put an end to the porpoising?



04-12-2009, 05:10 PM
first if you have not already check your engine set up hight etc but if thats done and you cant move the weight forward than the tabs will help the M120's would work well. I have them on my boat and they make the ride so much better.

04-12-2009, 06:58 PM
The M120 Tabs should work a treat. You would be better off with the bigger tabs than the smaller ones as they only need a slight movement in action before they start working.


04-12-2009, 07:04 PM

I have a 5.40 Cyclone large centre console that was also porpoising especially after I changed from the Merc 90 2 stroke to a Yammy 100 4 stroke.
I fitted Lectrotabs from Stones Corner Marine
They are made in the USA and come with 5 year warranty. All electric and easy to install. Only issue I had was making holes through the swim decks to fit them, which was a little bit tricky to calculate.
I can't believe what a difference they make. I wouldn't have a boat without them again.



04-12-2009, 09:57 PM
Thanks for the responses lads. Glad to see I'm on the right track. Hydro or electric? Well that's another argument I suppose. Mick, good to hear from a fellow Cyclone owner and it's nice to know the tabs worked.


05-12-2009, 06:06 AM
I bought bennets as my local dealer sells them and give great service.... I think they woud all be fine

07-12-2009, 01:09 PM
Hey Chucknduck,
I also have not been super happy with how my Cyclone is porpoising, I have a large centre console 540 with a 115hp fourstoke so it is also very tail heavy. Can you please expand upon your trim tab install i also have the same swim steps as you do. What kit number did you get for the lectro tabs? more photos of your set up would be help full also.

Cheers Jim

07-12-2009, 01:23 PM
so three out of three of these boats has a handling issue, and trim tabs (so it would seem) rectifies the problem! I put it to you, "how can they sell the boat (and why would you buy it) without the trim tabs as standard?" seems like either bad design or the makers are cheapskates, and the owners never had a test ride in one before purchase, one or all of those things!

07-12-2009, 02:16 PM
Yeah, see your point Noel, though I have a mate with the same hull and a much lighter engine (75hp 2stroke), more evenly balanced (more weight up front) and it rides beautifully without tabs, no porpoising at all. The hull themselves are great, just depends how you want to load it and what you want to do with it. Every boat is a compromise.


07-12-2009, 02:16 PM
Reading between the lines it's probably engine height and prop choice that is making the boat porpoise, which i guess is what Noelm is getting at.

Tabs are certainly a worthy fitment if chosen after the above two areas have been fixed.

cheers fnq

07-12-2009, 02:33 PM
a 90HP 2 stroke is not a heavy motor for a 5.4 metre boat, I reckon there is a setup problem (likely) or a design fault (unlikely) 2 batteries and a 90 on that size boat should not induce porpoising. Fitting tabs may indeed solve the problem, but it is probably only covering up the cause.

07-12-2009, 04:03 PM
Have you contacted the factory about this? They do have a bit of a rep for building a sh!t hot hull.....

07-12-2009, 09:05 PM
so three out of three of these boats has a handling issue, and trim tabs (so it would seem) rectifies the problem! I put it to you, "how can they sell the boat (and why would you buy it) without the trim tabs as standard?" seems like either bad design or the makers are cheapskates, and the owners never had a test ride in one before purchase, one or all of those things!

I bought my boat with the 90 hp Merc 2 stroke secondhand and it was fine but when I changed over to the heavier 4 stroke I got porpoising especially if there were more than 2 people on board.
The hull of the centre console is rated to take 115hp but I was already wary of the increased weight of the 4 strokes. I opted for the 100hp Yammy.
Now with the tabs I'm getting rough weather performance that I have better control over.
Jim, attached pic shows swim deck hole cutout.



07-12-2009, 09:26 PM
I opted for the 9" x 9" Lectrotabs. I have a transom mounted sounder so I was limited by the width, but even so I don't think they need to to be any larger either in width or length. They are very effective from low to mid position on their travel range .



13-12-2009, 03:00 PM
Cheers for the extra pics Mick, looks like a good setup i might copy. The porposing i am experiencing can be managed by putting a passenger on the seat in front of the console, this dramatically changes the boats ride. I love my boat and even though it does have a few quirks i would buy the same boat if i had the choice again. the hull is great in north queenland chop and although everyone claims it this hull is the dryest centre console of its size, notice porposing mostly when it glasses out and everyone sits/stands behind the console.


07-03-2010, 03:31 PM
Well, 3 months later I've finally got the tabs fitted. Hopefully I'll be able to get out soon to test them.

Ended up getting some Bennetts off E-bay at well under half what I could buy them for locally. Minor setback arose when I realised they were bottom-mount tabs but I've adapted them with the use of some stainless angle and bolts. Been in touch with Bennett in the US and they say this will work fine.

http://img40.imagefra.me/img/img40/2/3/7/scuttlebutt/t_wran9m_8d8e924.jpg (http://imagefra.me/view.php?img=/2/3/7/scuttlebutt/f_wran9m_8d8e924.jpg&srv=img40)

http://img40.imagefra.me/img/img40/2/3/7/scuttlebutt/t_wranam_c7acb01.jpg (http://imagefra.me/view.php?img=/2/3/7/scuttlebutt/f_wranam_c7acb01.jpg&srv=img40)

12-03-2010, 06:51 AM

They look good, let us know how they go.


12-03-2010, 09:12 PM
if u got fully lift up tabs on 2Nd photo i dont think it is correct set up or it is just angle of photo bin taken


13-03-2010, 08:03 AM
nah second photo the tab is down a bit, though it does look weird in the photo.

14-03-2010, 11:10 PM
Has anyone tried thge newer volvo trim tabs. They have been out for a few years and are smaller?

16-04-2010, 03:08 PM
Got the Cyclone out on Sunday to give the tabs a test.

Very impressed with the result. Was blowing about 15 knots in the morning and was able to easily keep the nose down and level the boat out heading across wind.

Improved the ride and handling out of sight, eliminated porpoising, also got onto the plane a lot quicker.

Best money I've spent on the old girl. As others have said, I wouldn't have another boat without them!