Footstrap Position and Speed

[agrelon]

Hi all,

I've just bought a 2006 JP Super X 106l and was blown away on my first outing by it's speed and acceleration.

I had the foot-straps in the outboard setting but only on the 3rd (out of 4) most back setting, and can therefore still move both straps about 2cm further back.

Does moving the straps further back generally increase maximum speed?

I would have imagined so as there would be more lift on the front of the board and less wetted surface area....

Any comments?

[mac33]

at your weight 54kg, moving straps to very back position would produce too much board lift, especially in stronger wind. i am another 12kg heavier, i have my backstraps as far forward as possible.

this helps to stop the board from taking off in gusts.

ask different sailors and some will say moving straps back is faster, a few will say moving straps forward is faster.

at my 66kg i try to reduce the lift of board as much as possible.

straps forward,weight in harness forward to nose, smaller fin,lower boom and high hook height all help.

a 5.8m at 54kg is quite large. a 4m + 5m will be faster for you if the wind is decent.

[agrelon]

Thanks for your advice. I think the same sort of thinking applies for mast track position... further back = more speed but less control due to more lift.

I had a 5.3m until 3 days ago when it got stolen from the place I stored it on the beach... So I'm with a one board and one sail for the moment. I do have a smaller fin though, which I can stick on my board if the wind really picks up to help me gain as much control as possible.

[Farlo]

JP SX106 has not much power in tail, and is not the most stable in its category. IMHO you will gain very little speed (if any) by moving the straps back. Some shapes work better globally with backward settings because you fly higher over chops. This one has a tendency to take-off already. A smaller fin will have a lot more influence on control and speed.

[agrelon]

Originally Posted by Farlo

JP SX106 has not much power in tail, and is not the most stable in its category. IMHO you will gain very little speed (if any) by moving the straps back. Some shapes work better globally with backward settings because you fly higher over chops. This one has a tendency to take-off already. A smaller fin will have a lot more influence on control and speed.

Next time I sail I'll try using my smaller fin (~30cm), footstraps completely back and out and mast track slightly back. I think with the smaller fin I should still be able to control the increased lift and might see some gains in top end speed.

Cheers.

[iago]

perchè parlate di tavole Jp sul sito starboard??


why talk of JP boards on the site starboard?

iago - my thoughts exactly

what about Futura or iSonic ??

[agrelon]

Originally Posted by Unregistered

iago - my thoughts exactly

what about Futura or iSonic ??

Because unfortunately I only have the money to buy second hand equipment and that a JP board was the best thing on offer. Trust me, if I could've gotten a Futura or even an S-type I would have.

As for posting on this forum, it's the best one on the internet for windsurfing info.

[Jean-Marc]

Agrelon,

I find that for your XS weight, a 36 cm fin is way too large with a 5.8 sail.

Never run that JP but I did use a Starboard Carve 111 with her stock 32 cm fin and a 5.4 m2 sail but the stock fin was way too large. A 26 cm slalom fin was a perfect setup up to 25 knots for my 65 kg, so I surmise the same should be fine with your 54 kg as well. A 36 cm fin was recommended for a 7.4 m2 sail on the Carve 111 BTW, so I'm pretty sure there is something wrong with your fin sizing setup.

Cheers!

JM

[agrelon]

Originally Posted by Jean-Marc

Agrelon,

I find that for your XS weight, a 36 cm fin is way too large with a 5.8 sail.

Never run that JP but I did use a Starboard Carve 111 with her stock 32 cm fin and a 5.4 m2 sail but the stock fin was way too large. A 26 cm slalom fin was a perfect setup up to 25 knots for my 65 kg, so I surmise the same should be fine with your 54 kg as well. A 36 cm fin was recommended for a 7.4 m2 sail on the Carve 111 BTW, so I'm pretty sure there is something wrong with your fin sizing setup.

Cheers!

JM

High JM, yeah I think so too. Even with the straps completely outboard I had to dig my heels in to keep the board flat. Also, I couldn't initiate carve jibes which was really strange.. but according to the Select-Hydrofoil website that is one symptom of having a too large fin.

I'm trying a 32cm today, I think it should be much better.Just put side by side, my 36cm and the 32cm seem to have an even bigger difference in size than 4cm, and the 32cm is much lighter. I'll post back on how this setup works.

Cheers.