This question came from one of my students one day. She just finished putting together her new kitesurfing board and wanted to try the board on and the straps were a bit too big for her tiny feet, so, she started to play around with the adjustments and soon she came to realize that options are few too many and she needs some additional information.
Well, here it is. The foot-straps should be loose enough so you can quickly get out of them when you choose to. For example, you just lost control of your kite and it started to pull you downwind and one foot of yours slid out from the foot-strap and the other strap started to twist your ankle causing some pain and you decide to loose your board completely for now. The tightness of the strap should not prevent you from detaching. On the contrary, the strap may be too loose.
A good measure of this is the position of your toes after a few minutes of riding. If your toes are hanging over the edge of the pad and you are able to touch the board with your toes than the strap is too loose. Another sign that your straps are too loose is if you want to lift your toes up and curl them up a bit when you ride. This also could be the sing that you may have positioned your pads too far forward, towards the toe side of your board and you may want to slide them back. One good analogy is to compare kitesurfing foot-straps with your house slippers. Not too loose, not too tight.
The tightness should be evenly distributed along the length of your foot (or feet I should say), heel to toe. If you feel more pressure around your toes than around the arch then you should re-adjust. Play with the angle of the strap, with the top portion of it. Even if two people have the same shoe size one may be more flat-foot and the other one may have a high arch and this calls for some adjustments.
Also, remember to make adjustments when you switch from wearing booties to barefoot or the other way around. A layer of neoprene does add up to the thickness of your foot, so, if you just put booties on, add more room to the straps.
When you are borrowing or renting a board from someone – prefect time to check how tight those straps are. When someone returns your board to you after some use, do the same – check and adjust.
One common mistake is to try to make the straps as tight as your running shoes. That would be too tight. You should be able to get out of those foot-straps easily and quickly when you decide to, bee it just at the end of your session or in case of an emergency. You should be able to detach from your board without touching it with your hands.
If your pads are of the right size yet your heels are hanging over the edges and your toes are far from the front edge of your pads, closer to the center, this means that you should open up your straps a bit more. Another sign of your straps being too tight is when you tend to stand on your toes when you ride. This also may be a sign that you need to slide your pads forward, towards the toe side of your board.
Dry straps will be smaller and feel tighter that the wet ones, this is why it’s a good idea to soak them up a bit before making the adjustments. Same applies to your harness, by the way.
Just for the kicks, try to ride your board without foot straps at all. You should be able to do this! Do not jump, and pick a place where the water is rather flat, no waves, and you should be able to cruise around just standing on your board and pushing down on the pads.
Also, remember that even though the pads are attached to the board with two (at least two) bolts, that connection is not designed for a forceful pull. You pull too hard on the straps, away from the board, and the screws may just come out from the board altogether with the nut. Happened to me a number of times. This would call for a repair with marine grade epoxy glue, but it’s a different topic.