THRUSTER vs QUAD - Buddy-x

typically a quad will be faster from the take off...more instantaneous speed, while a thruster tends to need to be "worked" a little more to get up to speed. quads tend to be "looser" than thrusters as well...depending on the shape (i'm not familiar w/ doc's shapes at all), the quad will really play into the "skatiness" factor of a board more than a tri fin would.
personally, i've found that quads take a bit more experimentation & patience to get really dialed in w/ the right fin set up, while thrusters are more "plug & play" for me. don't get me wrong, i've really been liking quads lately & have started getting the majority of my boards made w/ the tri/quad option, but i find that it takes more time & effort to really figure a quad out than it does a tri fin. but i still like thrusters, too.

 

I agree...

I like quads in smaller, weaker surf as they help generate speed better than thrusters. As the waves get bigger or more powerful, the emphasis shifts from generating speed to maintaining control at speed... at least for me... because the wave provides all the speed I need.

 

I have the K2.1 set and love it. I haven't really tried any other sets on this board but hey, its Kelly Slater. He doesn't just put his stamp of approval anything old thing that comes along. I'm actually trying to get that little 5th fin that he uses on bigger surf with the quad set up just for kicks to see how it works.

 

I think it's a great choice. I have a bunch of different quad sets and the K2.1 is my favorite. Definately my go to fins set up

 

I made my own litle 5th fin by cutting down another older fin and re shapping it. It makes the board ride like a single fin on steroids!!! Super fast and holds the line awesome!

 

i agree w/ LBCrew in that as the surf gets better, the emphasis switches to controlling speed rather than generating it, & for that, i still prefer a thruster set up. i did recently have a board made by brian wynn w/ the idea of experimenting w/ quads in better surf in mind, so we'll see how that plays out...can always run it as a tri fin.

fin-wise, i'm a bigger guy, so i've never used the k2.1's, but the quad rears from that set are my go-to quad rears for most boards. my favorite high performance quad set up is G-AM fronts w/ K2.1 quad rears. i just picked up a set of the MF-1's & am stoked to try them out the next time we actually have waves. i tried a "nubster" type fin in my hp quad groveler & was unimpressed...added lots of speed & hold, but stiffened the board up beyond belief. i think that it's something that's better suited to larger, steeper, or more powerful surf rather than waist high wind swell. i'll keep it in mind for my new wynn, but it'll never touch my groveler again.

the cool thing about the kelly fin sets is that the thruster rear fin is the same on both sets, so even if you just buy the k2.1 quad set, you can still try it as a tri b/c you have the k3's.

 

sorry, i may have explained that poorly.

on the k3 & k2.1 thruster sets, the center (rear) fin is identical. so if you want to try the k2.1 as a quad & a tri, you don't have to shell out the $120 for the 5 fin set, just for the quad set (which it sounds like you're already planning to do), b/c you already have the center fin from your k3 set.
just to clarify (from the fcs website):

k2.1:
Center

Base: 4.28" / 109mm

Depth: 4.41" / 112mm

Area: 14.22"² / 9172mm²

Sweep: 31º

Foil: 50/50

k3:
Center

Base: 4.28" / 109mm

Depth: 4.41" / 112mm

Area: 14.22"² / 9172mm²

Sweep: 31º

Foil: 50/50

 

glad that cleared it up...you won't regret picking up that quad set, though

 

quads are a bit more difficult to get up and going on your backside, i'm not exactly sure why though. maybe because they're looser and you're pushing it down with your heal? anyway, on waves where you're riding frontside, they're great for getting down the line or through closeouts. you do have to make a more gradual bottom turn on your backside though (or at least i do).

 

i just got my first quad and i absolutely love it man. really fast, lots of hold in turns, cutties, etc, and it takes off immediately. i have it on a fish and i wish all my boards were quads now. experiment man. it's the only way!