Apologies for topic bombing, but Princess Mary is Hot as!

Yeah, our crown prince really shot the parrot on that one! (good translated danish expression)

I don't think i am doing anything to cause the problems. I don't look at my gps while sailing, but topspeed after a spinout always say's 25-26. and i feel the rail bite a bit before i reach top speed on 30knot runs

I just lock in, and hang on. So i'm thinking it's the fin, but the size should be right. Could it be a weird situation where 25knot doesn't produce enough grip and 28knots produces too much lift?

Should i rake the fin back a couple of degrees? i'm guessing that the grip will not change but the lift will decrease.

Something that's stuck with me from a Peter Hart video:

He asks the two other experts if they think they can spin out on demand. They say "Sure, no problem". So off they go.

Peter says to the camera "I bet they can't"...

And so it goes. They come screaming back towards the camera, and at the appointed place push really hard against the fin, and all that happens is they rocket off upwind instead of spinning out.


Perhaps what's happening is that at that speed your fin and board are starting to fly and 'rail up'. This is normal, and part of the fun. Lean out more, keep the board trimmed flat, and accelerate to warp 9!!

Stuthepirate said...

Apologies for topic bombing, but Princess Mary is Hot as!

+1

Mine does it too...normally when I hit 40kts. Then I wake up (smiling) & get out of bed.

Put the fin across your knee and try to bend it. How flexi is it?
I have a 34cm fin that is very flexi and it produces much the same symptoms you describe. I think the flex gives the fin vertical lift, this pushes up behind you forcing the leeward rail down. This can also lift the windward rail allowing air to get to the fin causing spin out.
The other possibility is a foil thick at the front, this gives good low wind performance but can make to much lift at speed, and a very strong low pressure area near the leading edge, this can cause cavitation at speed.

whoever red thumbed my last post, if you don't believe how much a fin can bend, have a look at darrylg's post on the 2nd page of "flying the fin", in the GPS & speed sailing forum.

Some sailors like this effect, others don't. It may depend on skill level, rider weight, board set up etc, I just know I don't like it.

think I've figured out how to copy the picture over.



YES!!!!

There's hope for this old bugger yet.

Look at all that weight on the windward rail, and see all the spray from the leeward rail.
That fin is working!