Personally, i think a 4.7 would be too small for your weight in 5-15knots. I weigh 65kg and have a 116litre Starboard 7'11 and wouldnt consider using anything under a 5.3 in that wind strength. I think you would find that on the lower end of that wind scale you would be just standing there holding up a sail going nowhere and it most likely wouldnt pull you through the waves very well either.

Also, because you wont have the paddle, your going to have to use the sail to help turn the board so it will need to be big enough to provide power.

Personally at your weight I think you would be better off with at least a 5.3 or a 5.7 for that wind range. The modern sails are alot better than what you would have used 10years ago and are a lot more comfortable to use in the bigger sizes.

Disclaimer: Havent actually used a sail on my Sup, but, have sailed for 26years.

Good luck with it, i hope to try it soon as there are some crew doing it here in SA and it sounds like a lot of fun on small days.

I sail from time to time on my SUP.
All I use is a 5.3 (Superfreak).
Its enough for just a bit of slogging and when its getting big...I can use my waveboards anyway.

If I shift my target wind range up to 10-20knts will I get away with a 5m or even a 4.8m? I guess the stronger the wind the more chop on the water resulting in more difficulty not having foot straps on the board (I am not keen on screwing foot straps on and off all the time when changing between sailing and supping)

daddycool said...

I'm 100Kg and use 5.7 Gator on my Naish 11'2" and Starboard 9'6" in 5-15Knts. Fantastic fun for getting on a wave and reminds me of first days on a winsurfer back in the 80's

I remember the 80's and the first time I got a one design to a plane. We even took that barge out in big swell with a canoe paddle standing up – should have patented it then!

I sold all my boards when I got into SUP but kept some sails. I reckon the trick is whatever size sail you would have used on your sailboards go down a size. In almost no wind I can slog around on a 6.5 ezzy free ride sail, not cambered. When it gets to 10knots I use a 5.8 and it's nicely powered up. Btw I'm around 95 kg. I used to use the starboard blend (11'2) now on a starboard wide point 9'5. SUP IMO is not for blasting along at mark 2 with a sail on, it's for some nicely powered fun in the waves or flat water as to catch a wave you only need to be going as fast as you can paddle.

How come one is able to get normal surf board on the plane with a kite but not a sup and sail? Surely the rocker should have the same influence.

On Australia Day this year, I took my Starboard Drive (10'5 x 30') for its first sail. No real waves, just the swell of the bay down at Elwood. Still good fun, although with a little reef break it would have been GREAT fun!

Used a 6.1 in marginal winds (in about 11 knots). I weigh about 70kg.