My boat is mosly Carbon, and did not cost more than an A class; in fact it was almost 1/2!
Simon, from the above statement and the fact that your boat has cabon beams... can we assume that your boat weighs the same as an A class?? I mean: you have a Kite and associated gear so I will give you 5kg allowance for that, but your boat is 2 feet shorter than and A class. So I expect your boat will weigh in at ... say 80kg??
Or is your boat built with the special heavy weight carbon??
