Help! My fcs II H4 are not working so good in my Tomo Hydroshort. (FCS II)

Posted by Fin Guru on Jan 16th 2022

Posted by Fin Guru on Jan 16th 2022

Help! My fcs II H4 are not working so good in my Tomo Hydroshort. (FCS II)

Fin Guru FAQ (FCS II)

Name - Mike S.

Height: 5'9"
Weight: 173 lb
Board Brand: Tomo
Board Model: Hydroshort
Board Length: 5'10"
Board Width: 19  9/16"
Board Thickness: 2  9/16"
Board Volume: 31.4
Fin System: FCS 2
Fin(s) currently riding: KS 2.1 thruster and FCS II H4 TRI FINS
Please describe below what it is you are wanting more of out of your current fin/board experience (example - more drive, tighter turns, more release....etc) or any other questions you might have about fins or fin systems. Thank You.

I may be riding this board an inch too long and normally ride Futures but got this in FCS2. I surfed it yesterday with the FCS II H4 TRI FINS at Newport Point in head high sectiony/semi closed out barrels and it felt really drivey and pretty good but I have also ridden the FCS II H4 TRI FINS at River Jetties in NB and the fins didnt turn too well...not responsive. The KS2.1 felt more responsive. I normally ride Future Black Stick AM1's (medium) on my short boards which I really like. So confused as to maybe its the board doesnt like to turn. I am riding a Sci Fi2 in futures as my everyday board with the AM1 blacksticks. Just trying to give this board a chance before I get rid of it. Any advice would be appreciated.


Fin Guru Response:

Hi Mike,

Hmmm that sounds tricky - But i guess my first question is....How much better was the turning when you switched to the K21. I have heard mixed reviews on the H4 - but mostly it likes point breaks and open carves. I have not tried that fin yet myself - It's on my list though. Getting through a couple Futures right now.

The Am1 (medium) is similar to the K2.1 in regards to the smaller center fin which allows for that pivot all the while the fronts are supplying the drive. But the K2.1 is such a pivot fin. So im thinking if that didn't solve all the "Pivot" problems then i am not sure what would. The AM1 has a narrow tip which helps with release and response but the K2.1 fronts are so upright. But, Having said that The K2.1 do have a lot of surface area at the back of the front fins for that drive. There is one more Template that comes to mind. The HS Medium! It is a pretty unique fin. It has a very similar running base as the AM med. But it is upright and has a lot of area scooped out at the back of the fin making it a drivey yet pivoty fin.

The HS Med has a 31.8 degree sweep and the AM Med has 36.6.

The HS Med base is 4.50 and the AM Medium base is 4.55

So it's a tough call but that would be the only other set that i can think of that could work. It is a pretty dang loose fin. But it is a 125.00 experiment. I don't know anyone that has that board yet. So cant draw off of much second hand knowledge on the board itself.

hope that helps - let me know what you end up doing.


All the Best,

Fin Guru


These are the fins referenced in the this blog

https://usedsurf.com/fcs-ii-hayden-shapes-medium-tri-fin-new-fins/

https://usedsurf.com/fcs-ii-h4-medium-fin/

https://usedsurf.com/fcs-v2-pc-tri-set/