Its blowing 25 knots in the ocean at Leighton, the chop is ugly and I want to be as fast as the 90kg+ guys. Let's assume similar sailing skills.

What board is going to be most controllable and therefore fast downwind? I've no interest in slalom, just open ocean downwind blasting.

I currently have an Isonic 86 (also had an Isonic 76) – in the specific conditions above I feel I don't have the weight to keep the tail down and the nose up. At speeds around 32 knots I'm getting ready to bail.

If the heavier guys are also on 86's will I level things out by going smaller? Seems logical to me but what board?
Perhaps the Manta 54 (I think the Manta 49 is too short).
Others?

I used to have a manta 54 (74ltrs) and i am the same weight as you. I can recommend this board quite highly for the scenario you mention. AUS 1111 would be a better person to comment on tabous and answer this, i think he uses his manta 49 off Leighton from time to time.
I found the manta to be great in chop but a little sticky in real flat (sandy point type) conditions.
Other candidates could be a tabou rocket,rrd xfires or starboards futuras.

Judging by Recycle's recent efforts (and he is not a big guy) I'd say you already have exactly what you need in terms of the board. I would suggest trying different fins.

If you're trying to sail fast of Leighton then what you are really wanting to do is keep the board flat. Different fins have different effects on different boards but you will know you have the right one when it feels super slippery, doesn't lift the nose when overpowered but still has the lift to get you back upwind.

As far as the boards, I have the Mantas in 49, 54 & 59 and weigh roughly the same as you. The 49 is fun and can be quick in spurts but it is not quick over any real distance as you have to use too small a fin and it will lose the plot when things get messy. You can't sustain speed through rough water on this board.

The 59 is the go - you can use a 32cm fin and blast right over the messy stuff in a nice straight course.

Thanks Snides and AUS1111 for the replies.

I'm confused - if a 90kg guy is just holding down a 86l 55cm board with a 32cm fin then I would have thought to have a chance of going as fast I would need a proportionally narrower board and smaller fin? I have been using a Black Project S 26.5, much bigger and I seem to get too much lift.

In chop/swell, why does narrower not seem to mean faster?

In rough water / ocean conditions you need to be able to keep the board tracking nice and straight, and to do this you need a relatively deep fin.

The problem with using a small narrow board in rough water is that narrow boards need a short fin which just doesn't give enough directional stability. When the chop throws it off track it won't come back into line like a longer fin does. At 30 knots in the ocean you don't have time to trim the board for very bump so you have to let the fin fly and do the work for you - all you want to work on is keeping it straight and horizontal.

Incidentally, it is not really the riders weight but rather the (tail) width that determines which fin you should run in a particular board.

Hope this helps, and see you out there!

Thanks AUS1111 - a very concise and clear explanation.
I hadn't considered directional stabilty to be the main challenge. Makes sense though. I'll try my Falcon 32.

How would you compare the Manta 54 with the Isonic 86 re. controllability downwind?

Yes thanks Aus1111, good advice on gear selection. Could have used it on my one go at the Ledge to Lancelin.

We don't have an event like that on the east coast, whereas, with the L to L, the WA sailors include downwinding as part of their sailing repertoire. What other clues can you give us for small informal groups of downwinders?

We had a go yesterday, got nowhere near 30 knots, didn't maximise our GPSteamchallenge score but had a whale of a time.

www.gpsteamchallenge.com.au/sailor_session/show?date=2012-01-07&team=34

One thing we can improve on is communication.

Have you got a system of hand signals going on?

Such as

" too far out I'm going about "
"Let's circle here and wait for everyone"
"OK but had enough, pick me up from this nearest beach just here"


We found if the sailor in the lead does plop in the water to wait he will not be seen by those following, you need to keep your sail up while waiting.

We're not that organised Ian!

Mostly you sail around on a close reach pushing upwind, and whenever you feel the wind kick up a touch, just launch into a big downwind blast for a NM or more until your energy or bravery give out. Then you turn around and realise you are WAY too far offshore for safety...

In Perth the coast is 100% beach and the breeze is cross onshore so if you break something you will eventually make it back to shore.

There will be a few of us launching from Port Beach around 4pm this arvo. We'll push upwind to South Beach and then blast back down to Cott. If anyone wants to join in, you are most welcome.