I have a Tabou Rocket STD 125 (2013?) with a standard 44cm freeride fin (weighing 80kg with gear)
I have been sailing a NP Hellcat 7.7m regularly in 16-20knots (indeed overpowered), but feel like being lifted up by the fin (hovering couple centimeters above water) and losing board control (I can hold it, but need to depower or probably tail walking phenomenon happens?).

I have asked a similarly-isch question some weeks ago, but what should be the right freeride/freerace/slalom fin size for these situations?
Would a fin of 36-38 be better (too small, still too big?)

Which fin brands are the best?

try and move the mast base forward first, or lower the boom

Either sizes would be ok ,for me 38 .I use a MFC freeride ,(Maui fin company ) from surf& sail .
nice controlled fin and doesn't give excessive lift ,
maybe try using your 7.0 a bit more ,@80 kgs and 16-20 knots it would be a better size choice ,

I use mfc freeride 44 with my 7.5 on 125 Rocket, but drop down to a 38 mfc with my 6.5 sail. Much more friendly when overpowered and close to 30 kts in chop!

I had the same exact board a few years ago. As I weigh 90 kgs, I used an 8 ms sail and a 46 cms KP slalom fin in G10. I also used to spin out when pushing on the fin. To be honest I never thought it was tail walking. Instead, I thought it was the powerbox cast of this board not strong enough to support such pressures and that it was bending just enough that the fin made too much lift.
I couldn't find a solution and finally sold the board. I bought a fanatic blast 130 with a deep tuttle box and normally use a 44 cms slalom fin with it. I have never experienced a spinout since.

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Thomas123456789 said..

Which fin brands are the best?

The ones which cost more than your board is probably worth

Some G10 fins are quite thick to get the stiffness and feel slow and draggy. One of my Exocets came with an OE fin which I thought I would never use. I did try it, and it was as bad as I thought it would be for lack of lift and spinout when pushed. The previous Exocet board I used had a very good G10 fin, I used it all the time. I would say fins with a decent carbon content are better as they are thinner and less draggy.

I've had decent performance per $ from Choco slalom G10, Starboard Drake ready to race downwind slalom, Select Edge & S-Max. The best I've used is a F-Hot carbon slalom I bought secondhand.
Starboard's fins seems to have gone up in price a lot in the UK when considering the amount of carbon in it.
I've had no issues with Select fins, but a few here have.

This is not specific but the formula for boards over 115 litres should be sail size x 5 plus 4.

Thats an average, which is 7.7m x 5 = 38.5 plus 4 = 42.5cm

This is general really and can depend on sailing conditions and actual fin shape and is for medium winds or just powered up, so your 44cm fin is for light winds, 42cm for strong winds and 40 or 38cm when powered up.

Answering to which fin brand is best, I'd say again depends on conditions, sailing style etc, some fins suit cammed sails much better.
The Rocket is a FREERIDE board and not a free race board, and therefore something straight with a swept tip would probably work best.
Also consider putting the straps more inboard with a smaller fin so you are more over the centre line, and when over powered put your mast base a little more forward.

As far as brands go, theres some softer fins like K4 that work for wave boards, theres lots of others that use G10 or carbon, its one of those "What works for me" Types of question. Some people are more back footed than others so need stiffer fins. Try someone else if you can and see if it works for you and your board.

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Thomas123456789 said..
I have a Tabou Rocket STD 125 (2013?) with a standard 44cm freeride fin (weighing 80kg with gear)
I have been sailing a NP Hellcat 7.7m regularly in 16-20knots (indeed overpowered), but feel like being lifted up by the fin (hovering couple centimeters above water) and losing board control (I can hold it, but need to depower or probably tail walking phenomenon happens?).

I have asked a similarly-isch question some weeks ago, but what should be the right freeride/freerace/slalom fin size for these situations?
Would a fin of 36-38 be better (too small, still too big?)

Which fin brands are the best?

I had 115 (2014) and 135 (2015) Rocket for quite a few years (now have Rocket plus 105, 113, 125) and have ridden 105 & 125 quite a few times as my mates have them. I'm 90kg

44 is too big for the 125, which is 73cm wide (you can still use it - but not great when windy, as you have found out). I played around for quite a few years with different sizes and brands of fins. I settled on a 42cm for my 135 and 8.6, 40cm for my 135 and 8.1, 36cm for the 115 and 7.0

I've tried a 46cm (with the 8.6, also 44cm, and 42) however didn't gain anything overall, barely gaining any bottom, then losing the mid-range and top end due to more drag. This wasn't quite so apparent with the 115 and 36&38cm fins. Going above about 40cm, you start to notice the limitations of G10. The 44 was a Choco freeride fin, great bottom and overall handling characteristics, however is quite thick, hence the mid and top end speeds feel limited. The 46cm was a victor volt 11, which are my favorited G10 fins in the smaller sizes, however the 46 gave me no advantage over the 44 choco and no advantage over a 42cm Volt, there seem too much flex in the bigger fins, unless you go thick, which means more drag.

This is where Carbon fins come in. They can tune the fins stiffness by adding more carbon in the right places, but not having to increase thickness.

I've ended up settling on the Drake R2R carbon fins, 42 with my 8.6, 38 with my 7.8, and 36 with my 7.0. They go really well over all.

I've still got my Vector Volts, (34,36,38,40,42- sold the 46) and use these around rock and coal sites, as the carbon fins are quite easily chipped on the tip. I've also still my got my choco fins as well (44 and 38). I've also tried C3 vector fins (good top end average bottom end), which worked ok, however preferred the Volt

Overall I would be happy with any of them (Drake, Volt, Choco) in a 38cm for the 125 & 7.7. If you tend to be a bit hard on the tips of fins, G10 Volts would be my pick (still is).

Watch you're down haul settings, don't over down haul, as it tends to take the pressure off the mast foot. Also try moving the mast base 2cm forward of centre, when windy, to keep the downward pressure on the nose. Keep your boom slightly lower than you normally sail with. If you are still having trouble (after the changing the fin, boom height, mast foot, down haul) it might be the rig. Cammed sails offer better stability in the bigger sizes (7.5+).

My favourite for blasting around, was my old 135 & 8.1 turbo (twin cam) with a 40cm vector volt G10 fin. It so controlled all over. Rockets can be get up to have a high control factor, they are great fun boards to ride.

Thanks for all the response, gonna try everything everyone said and will change the fin to 37-39cm!

Can't wait to try it out