Hello, greetings from UK
I dont have much experience of multifin wave boards, my favourite wave board to date is an old starboard evo 70l single fin. In recent years I buy any board I find for a good deal, sail it on for a bit and if I dont like it I sell it on.
Anyway my question is
1. Do you need blanks for the finboxes which you don't use ? For example if you use a board with 3 finboxes as a single fin, would you notice much of a difference in performance if the finboxes are left unfilled?
2.Lightweight footstraps for wave sailing. Has anyone had any experience using them? I have heared from other people that even for slalom/blasitng they are too uncomfortable and not worth using. I have aquired a custom board around 90l which weighs in at 8.2kg (with straps, no fins), so anything I can do shave off a few hundred grams will be good :D. The original owner of the board said its made extra strong after snapping his 2 previous boards, so.no water inside the board (its been sat inside the house for 4 months without vent screw).
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TL DR
Do you need to use blannks on unused fin boxes
Are lightweight footstraps any good for wave sailing/freestyle
Thanks

Yes, you have to plug in blankers to avoid turbulence that will slow your board. Well, blankers add some weight ..ha-ha .. so its up to you. About straps- try the MFC- lightweight, comfy and rigid(very important feature imho). 8.2 kg with straps for a 90 l wave board is very much on the heavy side. This means later planning but better control in strong winds.

www.k4fins.com/product/k4fin-blankers/

I taped mine with my magic tape (see my site: windsurfing.lepicture.com/tips-and-tricks/) worked perfectly, no weight gain!

Yes you can use lighter straps, drake's seem lighter. They may wear faster. Depends on how you have them set and type of sailing/moves you do.

I like mine open all around and lean forward in them while twisting my foot to grab.