there was a discussion about this a few weeks back
www.seabreeze.com.au/forums/topic.asp?TOPIC_ID=48610not sure how many conclusive rules came out of it, but it was an interesting exercise with a calculator!
Get a wind meter so you know what's going on, both with the wind averages and the gusts and lulls.......the wind dynamics (the frequency of gusts and lulls, how large they are and how far apart) is the thing you have to understand....averages and forecasts don't mean too much.
I'm 75kg - when I was learning on my 135x40 twin tip with 11m and 14m C kites, my rules of thumb were:
10-12knots - practice flying the kite, self launching and landing. Not much point trying to ride on the water
12-16 knots - good wind for learners to practice riding, although getting upwind will probably still be a challenge. Not too much power in the kite.
16-20 knots - proceed with care, be ready to use your safety systems. If you have some basic skills down, you'll find that this wind strength is the easiest to crack the upwind riding.
20knots plus - sit on the beach and watch and learn from the more experienced riders
