Of note he recommends a universal to foil mast distance of 75cm for windsurfing (not sure if that refers to just the shred sled). Also talks about pumpability/stability of short versus long fuselage

That probably depends on the equipment. 75 cm is FAR TOO SHORT for most of us mere mortals on most equipment. 107 cm is more like it most of the time.

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segler said..
That probably depends on the equipment. 75 cm is FAR TOO SHORT for most of us mere mortals on most equipment. 107 cm is more like it most of the time.

I guess it depends on board. I sail RRD Pocket Rocket and most forward position of mast is 105 cm from front bolt. I set mast around 98-100 cm, and it works fine.
I guess I have to add: I'm using SS I84 (in C) with 48 back wing most of the time. Sails 5.7 and under.
Riding strapless.

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segler said..
That probably depends on the equipment. 75 cm is FAR TOO SHORT for most of us mere mortals on most equipment. 107 cm is more like it most of the time.

Yeah there are lots of variables beside foil mast and sail universal placement, the main one being how close the front foot strap is to the universal

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segler said..
That probably depends on the equipment. 75 cm is FAR TOO SHORT for most of us mere mortals on most equipment. 107 cm is more like it most of the time.

Interesting. I'm find 94-97 cm comfortable with the i84 in C position (old slalom board, sails up to 6.5). That would be around 100 cm in B position.

We also have a 7' JP Foil SUP. The maximum possible distance for it is 81 cm, but that would put the back foot pretty far before the mast. My wife windfoils it with a distance of about 74 cm for the i84. I have tried that, but it was a bit beyond my skill level as a mere mortal. It's possible that I could learn, but it would take a few sessions, and sail sizes would be limited to < 6 m.

We also just got another 6'10" foil SUP that has the foil tracks mounted ~ 10 cm further to the back, and allows you to stand almost 20 cm closer to the tail than the JP. It also has a mast track, which allows for a distance of up to 100 cm if the foil mast is far back, and the mast foot all the way to the front. But having the mast foot so close to the front makes slogging rather hard, at least for someone not (yet) used to short board, since most of the volume is in the tail. Like the JP, the board seems more oriented towards the wing (and perhaps wave SUP use).