Do others have issues with pushing the foil aggressively upwind at speed and suddenly it feels like your foil just blows out??

I have heard air can make it down the mast and cavitates the foil.

Wondering if there is anything I can to reduce this from happening so much...

I was thinking mast flex but you're using Axis mast. I use the even longer 1050cm Axis mast and don't feel mast flex, but when I had a cracked rear wing, it gave a similar feeling occasionally, before I replaced it.
19mm width mast is the one I use. Are you using 16mm or 19? I use a similarly sized front wing as your 1210 Takuma and I weigh ~200lbs.

I have a feeling it is possibly the foil section on the Axis alu mast causing ventilation. Not that it's a big problem or a bad mast (it feels nice and stiff), but I felt the same thing riding Tweezer's alu Axis/999 pushing hard upwind. I'm pretty sure he's experienced it a fair bit too. I think it doesn't tolerate this loading as well as some others. Some complained about Armstrong's V1/V2 masts ventilating occasionally when being pushed but I almost never had that problem. I feel like the new Army mast goes upwind super well and I know they changed the foil section to try to eliminate ventilation, so perhaps the Axis suffers a little from a foil section related issue. Maybe chat with other Axis guys and see if they have a technique to mitigate this?

I have noticed this issue with my Axis setup. Usually when it happens now I stomp on my toes of my rear foot to right the board back flat and I can save it. I think when I have a steep upwind angle at speed I keep the mast from laying over on a steep angle and lean outboard and forward more with my hips if that makes sense.

Thanks for the responses...

Yeah I was thinking its the mast... I also have a bigger board (110L) plus me and my weight might be adding to some flex.

@MrNorthSouth yesterday in the big winds, I was noticing if I focus on not putting too much angle on the mast while pushing hard up wind it improves....

I have an 80L takuma hopefully arriving soon, interested to see if that improves it at all.

If you're on the takuma 1210 I saw in your log, then my vote is shallow angle wingtip breach ventilation. I can't see that front wing being fast enough to cause mast vent. I find my foils breach well under medium/low speeds and steep angles, but at high speed, fast upwind through cutting through swell I get the blowout on my w1000, rarely on the w800 using the same mast.

Make sure all you gear is clean, apparently wax or oils on the foiling stuff can propagate venting. If you have a faster front wing or one with a shorter span, then throw that on and try to push it. Shorter span is less likely to wingtip breach under the same angle/load. No way it's flex. Axis aluminum masts are crazy stiff, especially with something the like a 1210 under them. I've ridden some seriously wobbly masts, and they feel shaky and unstable, to the point you won't even get going fast enough to blow out.

TunaCan wrote: ↑Mon Feb 06, 2023 1:20 pm Do others have issues with pushing the foil aggressively upwind at speed and suddenly it feels like your foil just blows out??

I have heard air can make it down the mast and cavitates the foil.

Wondering if there is anything I can to reduce this from happening so much...

The Axis alum mast, while it offers affordable stiffness, has its limitations. The foil section on the mast is known for cavitation. Project Cedrus attempted to produce a stiff Aluminum Mast that wasn't as prone to cavitation with some success.
There are a number of videos online, in addition to discussions about the subject in the forums. Try Standup Zone and Seabreeze Kitefirumn if u want to dive into it a bit more.