After being infected by the speed bug at the speed event at Sandy Point I have decided I may as well try and get a board more suitable for speed sailing. Instead of going the normal route (like normal people) and buying something already up to the task, I have decided to experiment a bit and see what I can modify, to do something similar.

I have bought a damaged 2005 JP RWW 76L board and have already added a powerbox to it and added twin footstrap inserts to the back. The next thing is to add some inserts at the front footstrap positions so that they are much closer to the rail.

So, I guess at this point I am asking 'what is special about the shape of a speed board'? Does a wave board have too much rocker to be useful as a speed board? If I modify the rocker and the vee, what should I aim for? It seems that when up to speed, the board only really sits on the section from the front straps back, so does the rest of the board matter?

...Yes, I know I should have used a tuttle box, but I already have some good powerbox fins... the next version can get the tuttle box.

Ian K said...

... I'd be interested to know how a slalom fin and outboard straps have affected yours? I'm starting to think that the subtleties of board shapes are not that important.

Hi Ian. I am lucky that a mate has the exact same board and I should be able to compare the differences as I go. When sailing his last Saturday I noticed the footstrap positions are obviously set up for waveriding. It also has a us-box, so I guess I have the opportunity to try a few different types of fins compared to the typical us-box range.

The tail rocker is an area I have been wondering about. It should be easy to fill, but what differences do you think it will make?

Doesn't Tony Wynhoven mainly use wave boards at Sandy Point and regularly posts 40+ knot speeds? It could be Craig Spotiswood....not sure which of them
Anyway, they prove obviously that a lot of the speed comes down to ability and quite possibly the rig and fin as opposed to mainly being the board. A speed board may be more controllable due to its tail shape.
Just my 2 cents worth of thoughts on the matter

Ian K said...



And we've both spoken to the worlds fastest 60 yo who tells us that at speed on flat water there's hardly any of the board in the water so "What's it 'kn matter?"

Well, in that case, my formula board should be okay then...

It's interesting looking at all the photos that Jodi took of the event to see where/how everyone's board is sitting on some of these runs. I am assuming that not many of the photos were taken on really really fast runs, but none-the-less it does show you how much board is in the water. More than I thought in a lot of cases, but still not much.

I can speculate and say that the low amount of tail rocker helps with the way the water releases from the board, but that's just a guess.

As you have suggested, this is in flat water. I expect that sailing around Sydney means that the board shape will make a bit of difference too as it aint quite as flat as SP.

Hey Formula, I'm on a similar project at the moment modifying an old bic adagio slalom board. The main problem with the old board being too long and the distance from tail to mast track too far, as was normal back then. So I've chopped both ends, reboxed with powerbox (yep too many pB fins to go over to tuttle). May need to put some new front strap inserts in as the stance is now a little narrow but that can wait. I'm just guessing on the rockerline but I've ended up with flat for the last 40cm, then another flat of about 80cm (original rocker line). Here's a couple of pics.




I've also raised the nose rocker a little and softener up the forward rails that use to catch in the chop. Also need a respray as the psycho graphics that were cool when I was 20 something are just too much now

Hi Rex,
THere's a good chance the board won't do anything special as I'm not a fast sailor anyway, so its just a hobby sort of thing using an otherwise worthless board.
My thoughts on the balance of the board was mainly to bring the board more inline with modern board design. Most boards seem to have their mast tracks centred around 130cm from the tail, the old adagio was by memory about 155cm so instead of moving the track aft I've shortened the tail. Most boards nowdays are between 235 -245 long, so I've chopped the front as well to get a 235cm board. These measurements are fairly common to see on modern slalom boards of 57cm width so I'm hoping it will work out.
But I'm not gonna lose any sleep if it sails like a dog.

that looks familiar

It needs a name. I was thinking the " Love muscle 62"
I,ll probably get sensored now!!!!

Here is my Speed Board Retro Fit.
Started life 15 years ago as an old 9'2" Course Slalom board.
Board was originally built "light & stiff" overloaded with carbon, 10mm foam core carbon stringer on the bottom forward of the fin box, carbon uni under the foam
core with Full Carbon wrap.

To Retro:
1st/ The Deck, Rails, fin box, mast track was removed.
2nd/ Rails & Deck reshaped, wooden deck vacumed on.
3rd/ Cuts out added to improve board trim from the old rocker shape.

Result:> 4" thick, 47cm wide, 240cm long, 30cm wide tail. Top Speed so far 43 knots
(25 knots of wind).

Conclusion: Time wise its easier to build from scratch, only reason I retro this
build was the carbon content.

Next Board starts from the Computer & then Precision Milled.

mr love said...

It needs a name. I was thinking the " Love muscle 62"
I,ll probably get sensored now!!!!

So you want a board that is small and meant to finish fast named 'Love muscle'?

Nice one Icesurf, those are pretty serious cutouts. I had some smaller ones in mind but will think abit more on that yet.

Mr Love, you seem to have a nice shape to the 'muscle' what density foam are you using and whats the plan for your layup? Any estimate on final weight?

Icesurf -

Pretty serious 3 axis machine you are building there! ARe you going to do boards or going by the beefiness of the rig something heavier? must of cost a bit for those lead screws and linear rails. Im jealous!

Ian K said...

Well I've just added 8mm on to the tail of an old 84 litre Jp wave board, reducing its tail rocker from 10mm to 2mm. Doesn't seem to go any faster, but it gybes beautifully,

if you used bogg i'm sure it would make the tail to heavy, the best way to do it is to glue some 8mm vivinicell and fill the divi with bogg dont worry about glassing, you can then take the board out and see how it goes and if you need to play around with it
i'm sure the thing that makes a slalom board quick to plane and it's speed is a flat profile( if you fill the tail rocker on a wave board you still have to much nose rocker )
last winter i made a slalom speed,1mm tail lift,2mm at 1,200 and 170@ nose and 520 wide with cutouts,the cutouts made the tail a bit loose so i filled them in.
what iv'e noticed with the tail lift is, the splash comeing from the board is further back than my slalom and sailing more off the fin, even with such a low nose rocker the taillift made the nose lift in shoppy conditions so the finbox needs to be about 20mm forward and that should keep the board a bit flatter,