I'm having a problem with my new board the JP Slalom V 76, I love the feel and performance of this board, but my front foot keeps slipping out of the strap!!

WTF am I doing wrong? How do I fix this? Hopefully its not the ergonomics of the board?

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hardie said...

I'm having a problem with my new board the JP Slalom V 76, I love the feel and performance of this board, but my front foot keeps slipping out of the strap!!

WTF am I doing wrong? How do I fix this? Hopefully its not the ergonomics of the board?

try a bigger fin. lower boom a tiny bit. Works for me.

Good to See you surviving Hardman, I pulled my front foot out once going for it and before my brain could say poop, it was all over red rover and one fornicated boom

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Bender said...

hardie said...

I'm having a problem with my new board the JP Slalom V 76, I love the feel and performance of this board, but my front foot keeps slipping out of the strap!!

WTF am I doing wrong? How do I fix this? Hopefully its not the ergonomics of the board?

try a bigger fin. lower boom a tiny bit. Works for me.

What he said Hardie the fine adjustements and it will lock in.

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hardie said...

I'm having a problem with my new board the JP Slalom V 76, I love the feel and performance of this board, but my front foot keeps slipping out of the strap!!

WTF am I doing wrong? How do I fix this? Hopefully its not the ergonomics of the board?

The balance is out with your sail's Center of Effort too far back. You can rectify this by either moving the mast base forward or downhauling the sail more to move the C of E forward and down.

All this will work but the best thing to do is to balance the board out to begin with.

There are a few Golden Rooles to set up a board, they are the starting point to get everything in balance.

1. Measure 30 cm in from the tail and measure the width of the board at this point.
2. Pick a fin with this depth and fit to the board. (start with a normal upright fin not a weedie)
3. Make sure the rear foot strap is mounted with the rear screw in line with the leading edge of the fin.
4. Set up the front foot strap by laying your arm on the board with the elbow bone in the middle of the rear strap and measure to the tip of your middle finger.
5. This point will be the middle of the front strap, mount the strap as close as possible to this position.

Your board is now balanced to your body, the foot strap position will be different for each sailor.

Put you mast foot in the middle of the box and go sail. Once you're comfortable you can fine tune the board further with different fins, mast foot further back or forward etc.

Hardie,many of todays boards are set up with the straps too far apart for us normal sized speed sailors.Roo,s guide for the front strap is spot on for me and the only boards that have got it right for me was the Kids pro and the CA 40. Check out Tom,s web site for an easy way to move that front strap back beyond the exsisting holes with out stuffing the board. Either that or sell the board

Dead right Kato, 55cm between the straps seems to be the standard and far too big spread for average sized sailors.
No doubt the sizing was built around 6'6" gorillas in the early days of w/surfing.
The slalom boards of those days didn't want to do anything except go straight and gybing needed the front strap way forward.
I've moved many front strap inserts back 4-6cm for shorter people and no negatives.
Small ladies in particular need straps up to 11cm closer in order to get the same leg angle as the 6'6" man.
Board builders seem very reluctant to change from these original dimensions as they believe gybing is compromised but it seems the modern shorter and wider boards gybe so much better that straps further back are no problem.
Haven't heard that elbow to finger tip (from Roo) before but that is right on.

Slalom V 76
Sails:
ideal: 7.8-9.0
rec.: 7.2-10.0

Recommended fins
42cm......<7.0
44cm.......7.0-7.8
46cm......7.0-8.2
Recommended fins are slalom not weedies

6.7m sail is a bit undersized as is the 36cm weedie
that said the board does trim very nicely with this combo

I picked up a Hypersonic a while ago and had been having major trouble with my front foot coming out of the strap. I tried a few things like footstrap position and boom height with some success but moving the mast base forward made a HUGE difference. I haven't had the opportunity to use the board much so this has been a long process but last weekend I finally got the magic carpet ride these boards are supposed to produce. Might go out now and measure how far off Roo's settings I am.

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Roo said...

hardie said...

I'm having a problem with my new board the JP Slalom V 76, I love the feel and performance of this board, but my front foot keeps slipping out of the strap!!

WTF am I doing wrong? How do I fix this? Hopefully its not the ergonomics of the board?

The balance is out with your sail's Center of Effort too far back. You can rectify this by either moving the mast base forward or downhauling the sail more to move the C of E forward and down.

All this will work but the best thing to do is to balance the board out to begin with.

There are a few Golden Rooles to set up a board, they are the starting point to get everything in balance.

1. Measure 30 cm in from the tail and measure the width of the board at this point.
2. Pick a fin with this depth and fit to the board. (start with a normal upright fin not a weedie)
3. Make sure the rear foot strap is mounted with the rear screw in line with the leading edge of the fin.
4. Set up the front foot strap by laying your arm on the board with the elbow bone in the middle of the rear strap and measure to the tip of your middle finger.
5. This point will be the middle of the front strap, mount the strap as close as possible to this position.

Your board is now balanced to your body, the foot strap position will be different for each sailor.

Put you mast foot in the middle of the box and go sail. Once you're comfortable you can fine tune the board further with different fins, mast foot further back or forward etc.

Well I'll be buggered I am one of those guys, where my coit is closer to the ground then the average 6'6" guru.
I am always belting the bejesus out of my toes going into the rear foot strap and feel unbalanced to a degree most times
I just went and measured the last of my JP boards (JP 91lt Supersport) I have.On injury mid level list at the moment
Using these calculations, I need to move my rear strap to the forward hole to line up with the leading edge of the fin (about 20mm or 3/4 inch) and move the front strap back about the same so as the "elbow-middle finger" calculation comes into play.
That's some adjustments I will be doing soon as I can get back in the saddle. Thanks Roo

The basis for the elbow bone to finger tip measurement is related to shoulder width. The most stable stance is when your feet are approximately shoulder width apart. Stand with your feet together and knees slightly bent. Have someone try and push you over. Now stand with your feet shoulder width apart and see if they can push you over. As it happens the distance from elbow bone to fingertip is pretty close to your shoulder width for a grown adult. It's an easy way to set your foot strap position without getting a tape measure out.

Having the same issues with a JP II 84! This is just what I've been looking for. Cheers:-)

Ditto for me with my jp fsw 92. I put a post in here a couple weeks ago about my inability to find a nice balanced setup with my 6.2. In also pull my front foot out. I find it much better with my 5.0. I am going to try this setup advice and see how it works for me. Thanks for this! Is there anywhere else I can find other tips like this for recommended boom height, mastbase position etc. Ideally I would like to find the ideal starting point for my setup for my body including footstrap position, mastbase position, boom height, harness line position etc.

Thanks again!!

-- Adrian

You can get some good pointers from www.guycribb.com, go to the technique section.

Figured I'd put all the Golden Rooles together.

There are a few Golden Rooles to set up a board, they are the starting point to get everything in balance.

1. Measure 30 cm in from the tail and measure the width of the board at this point.

2. Pick a fin with same depth as the width you measured and fit to the board. (start with a normal upright fin not a weedie)

3. Make sure the rear foot strap is mounted with the rear screw in line with the leading edge of the fin.

4. Set up the front foot strap by laying your arm on the board with the elbow bone in the middle of the rear strap and measure to the tip of your middle finger.

5. This point will be the middle of the front strap, mount the strap as close as possible to this position.

Your board is now balanced to your body, the foot strap position will be different for each sailor.

Once you've balanced your board it's time to look at your rig. If you've set your sail up using the recommended mast and according to the measurements on the sail then it will be easy to balance it out.

1. Take your fin out of the board and connect your sail to the board with the mast foot in the center of the mast track.

2. Stand the rig up and with the board on a flat surface, i.e. grass or your board bag for protection, stand on the board with your feet either side of the mast foot.

3. Move the boom until its around shoulder to chin height.

4. Lay the rig down and measure from the front of the mast at the boom to the clew eyelet.

5. Divide this distance by three and measure from the front of the mast at the boom back this distance.

6. This is where the center of you harness lines should be. Grip the boom here with both hands thumb to thumb either side of your measurement point and place the harness lines either side of your hands.

7. To get the right harness line length grab the boom in the center of the lines and adjust the lines until they are just touching your elbow bone.

8. Most sails have their max draft around 33% so this is a good balance point for most sails.

9. With the board and rig still connected, lay the board on its side and the rig on the ground, tilt the rig towards the back of the board until the gap is even between the foot of the sail and the deck of the board.

10. Your mast foot is in the right position if you take a line perpendicular to the board, i.e. at a 90 degree angle, from a point midway between the front and rear foot straps and it lines up with the center of the harness lines. If the center of the harness is too far forward move the mast foot back, if its too far back move it forward.

11. Put your fin in the board and go sail to see how it feels.

Now you have a reference point you can set the board at each time you sail, it makes it a lot easier to fine tune your equipment for optimum performance for the conditions.

Remember if you're not fast...you're last!

Thanks Roo, Good advice. Though any suggestion for when step 4 & 5 doesn't work? I've got my aft straps on the fwd holes holes and the front straps on the aft holes, yet when I put my elbow at the centre of the aft strap its still short of the fwd strap centre by about 50mm.

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Scottda said...

Thanks Roo, Good advice. Though any suggestion for when step 4 & 5 doesn't work? I've got my aft straps on the fwd holes holes and the front straps on the aft holes, yet when I put my elbow at the centre of the aft strap its still short of the fwd strap centre by about 50mm.

Two choices: have some new foot strap inserts put in the board or make up some stainless plates to bolt on and move the strap location.

What would be the result of having the rear footstrap too far back?
Could this lead to someone being too heavy on the back foot, spinning out etc?
Just curious as my neutral position on the rear screw seems to be about midfin...tabou rocket/powerbox.

The guide is just a starting point to balance out your gear. A lot of the world cup Pros ride with the rear strap further back and larger fins than recommended. If you have the skill and strength to do so it will work but the chance of spinout is increased if you don't know what you are doing. Also on the very wide tailed boards that create a lot of lift you may need to move the straps back to balance out the board when using larger sails.

Cheers Roo, it's a good guide too. After feeling like a crash test dummy for the last couple of years it's all starting to make sense. On paper anyway

Hopefully its not the ergonomics of the board?

i think it probably is.

my isonic i76, i refuse to use as i keep coming out of front strap.

in rough conditions this is so slow + dangerous.

my advice move the back strap forward to max, then get new holes put in for front footstrap position.

front strap position new holes a little more parallel than before + futher back.

i did this on my old sonic, it did solve the problem.

i am going to get this done on my new isonic76.

I had the trouble with my foot coming out of the front strap on my i86 when I 1st had it, but when I fully downhauled the sail, and put the harness lines in the correct place, the problem went away. I'll try moving my straps as per the guide as close as possible, but I would have to make some mods to move the front straps back as per the guide