Thruster/Quad combo question

I have a question regarding boards like the CI Quad that give you the option of riding the board as a quad or a thruster. I am thinking about ordering a board like this because I have been wanting to try a quad but if I end up not liking it or only want to ride it as a quad in certain conditions I would want to ride the board as a thruster. My question is whether, having to compromise between the two fin configurations, the board would perform like a standard thruster or is there a difference in the placement of the forward fins that would affect the performance.

Hey saucyjack,

         check out this link they talk about fin placements and how it affects the board's riding characteristics.

If you email the guys at probox they probably give you more info on quad set ups telling you how fin separation from end to end and cant can change the way your board rides.

robin mair is a fin genius. that is all.

Aloha saucyjack:

It certainly is very possible to setup a board so that the fin layout works for both scenarios. My quad layout typically has the front fin in the same location as I would place them for a thruster. So the simple answer is yes it can be done.

I think though that the biggest variable is going to be the fins! Experience has taught me that certain fins work better for a quad setup than a thruster, at least if you want them to work optimally.

The other thing that we have learnt is that the cant angle of the fins makes a difference between the two setups, so with a fin system that does not have cant adjustment you are going to have a slightly harder time optimizing the fins, or you will end up needing a larger variety of fins to optimize the setup by having to have different cants in the bases of the fins. This can get very expensive very quickly!

Hope this helps!


I’ve had my first 5 finner (thruster or quad) for 3 months (6’2" x 19.2" x 2.4") traditional performance SB swallowtail. I rode it first a few times as a thruster to set my performance baseline and then (and ever since) switched to a quad … even with all the great (thruster) fins out there, I don’t see ever going back. Just surfed it in 6’ to 10’ faces in Puerto and longer peeling points both rights and lefts for 6 days. I had been riding the FCS M5 and PC5 in front and GX in rear (and thought it was incredibly fast and responsive), but switched the front fins to some older Carbon K Fins and it lit up even better… you could feel the point at which engaged off the bottom. Just a crisp, pivoty feel of a thruster, but the speed and flow of a quad.

I say everyone should be building them … have fun.