Select to expand quotecolas said..Daveb27 said..
Coming from a prone surfing background, I think width slows down rail to rail transitioning and trimming, which can affect performance.
This is true, but I found out that it is also true of high volume (thick) rails.
And we have then two competing factors: More width raises latency in rail-to-rail... but also allows the shaper to "spread" the volume on a bigger surface, and thus reduce the rails volume... which helps rail-to-rail.
I was convinced that narrow was the way to go for quick rail-to-rail, but after using boards somewhat wider but with rails thinned as much as possible, I am not so sure... They paddle slower, that's for sure (width and thin rails both add drag), but on the wave I think I am enjoying them more.
Notwithstanding the fact that width and rail shape are only two of the many factors that effect board design and their 'turnability', this makes a ton of sense to me. A big part of SUP for me, tho, is early wave entry. So I like the speed of a narrower board. Especially important in a crowd bc if I don't want to be the guy who paddles for waves and doesn't make them. But the stability of a wider board is also important, bc I don't want to be the SUP guy constantly falling in the line up. Compromises...
Select to expand quotecolas said..
width adds drag, but:
width also increases the lift force while planing. (this lift does not comes from nowhere, thus it adds drag)
So, if a board is just around the lower range of planing speeds (i.e. surfing in slow waves), more width can make the difference between slogging in displacement mode (longboard glide) and zipping in planing mode (fish accelerations).
In a nutshell, narrow boards are generally faster, except when you are feeling the waves are so slow that you find your board tends to bog down. Then either using wider boards (for lifting it more out of the water) and/or shorter ones (for lowering the range of their planing speeds) can make you surf faster. This is why short small wave boards are generally wider.
nailed it as always
