Hi Sebastian, I would suggest keeping the 80 litre board as its a good size, then maybe add a board in the 70 liter 50 wide range, Manta 49, JP50, Falcon speed , etc ... this size will be perfect with your 5.7
Cheers
Ian
Take a few steps maybe?
First get comfy on your smallest board also in its lightwind range and only then go to a smaller size in mid-highwind range.
With your weight it is definately possible to sail boards of around 65 liters, but you need time on the water to get used to it.
Boards that Ian mentions are definately good options.
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