I have been sailing a Lorch Div S 83 speed board for a while now(225 x 49.5).
At first I hated it including a spin out crash at 35+knots. It would let go at random.
But as with so many boards a bit of tweaking has turned it in to a very versatile board despite its unusual shape.
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I found that moving the back strap forward cured the spin out problem but I have not been able to get the top end speed out of it I would like.
One of my earliest sessions got a 37.5 but recent sessions have been 36 ish max.

I checked the rocker and there was a slight negative in front of the fin. Refaired it and had a good session on Sunday where it felt like it was accelerating better. Wind was strong /gusty but I was topping out at 34.8 (4 runs) apart from one squall for a 35.5.

Looking at Realspeed the runs are very peaky which has always been my speed issue.





There was short chop but it was not bad. So finally getting to my questions for the gurus:

1. How do you make a small board/ small fin (49.5 wide, 24cm 45 degree weedy, 6.3 Loft Racing Blade on rdm) go faster across the wind to be able to benefit from the slingshot? As you can see from the images my fastest run had an entry speed before the bear away of about 28 knots(2nd 27)

2. How can you maintain board speed after the slingshot in chop? Six seconds after the peak I am down to sub 31 knots(2nd 30). Bear away is about 40 degrees by the end of the 10sec on fastest (2nd 35)

Looking for suggestions on fin type, size but still keeping the stability through the chop and any tuning tips. (Sail is bagged to touching the boom between the harness lines and mast position has been varied)

Thanks in advance for putting up with the long winded post and looking forward to the discussion.