I just had a session on a board, 8’6" rounded pin with single into double concave through the tail, thruster fin set-up, nothing very radical.
My impression was that it wanted to ride “high” on the wave, up in the top third.
Could this be due to the concaves?
(I normally ride vee bottoms)
Rails???
Any “belly”
or maybe chines.
Last two could be the trouble.
What is wrong with riding in the top third of a wave? that is where the speed is. the problems I have noticed is when a board will not release and “tracts” or sticks there when you want to set a different line to get around sections. This is often caused by wrong fin in wrong place.
The white beard of knowledge has spoken. Heed his words.
hmmm. noted. thx
all the best
Yes I feel it does track in that position and not respond as well as expected to input.
It has fin plugs set up as either thruster or quad option, and I was using thruster set up with mid size fins.
No real option of changing positions.
What fin set up should I try???
There is a potential physics explanation as well…
I’d surf it more towards the tail, and engage a little less rail.
If there,s a physics theory that will help my understanding I’d like to hear it.
If anyone has a suggested fin set up to try, I’m interested as we’ll.
Just as an experiment I replaced the front thruster fins with larger ones (twin fin size) and gave that a go in some head high waves. Not sure what to expect.
I felt it did reduce the high tracking but did feel some extra drag?
On a good wave, surfing right on the tail it went well as it should.
The problem occurs when trimming or in a weight a bit forward situation, where as suggested there is more rail in the water. That’s what made me wonder about concave and maybe that effecting the bottom rail shape?
It is always helpful to show some pictures of the board.
My go-to longboard is an 8’0 single to double, and when I want it to trim more I ride it as a single. I only put the side-bites in when it is a bit steeper and faster. Works well for me. I find flat bottoms trim better, but they turn slower than do concave bottoms. Changing fin configurations allows me to adapt to different conditions without changing boards. Also, I use a smaller rear fin (7.5") on this board.
“Could this be due to the concaves?”
There are lots of potential causes but yes, especially if you’re used to riding vee bottoms.
Maybe ditch the sidebites and ride it as a single. A fat foiled single fin if you can find one that fits. One that doesn’t have a big fat tip on it … like a standard ‘tuna fin’ sort of thing. Something that won’t ‘catch’ water flowing up the face as much.
The fin plug set up on this board is standard thruster set up , with extra plugs to convert to quad.
No centre box for single or single with side bite options.
I’ll just chuck in different combinations and see what feels best.
I’m still leaning towards the difference being between the vee bottoms I’m used to and the new concave shape?
Based on your last post, I’m thinking the fins may be more the culprit than the contours.
Yes, have had posts suggesting fins, but no explanation as to how or why that is so.
Would love to hear how it is the fins so I could then try to improve the situation?
there’s not much I can do about the bottom, but at least I could play with fins.
