One of the things you need to consider in set up is how you sail also.

Pre-bend in the mast should be set to fit the cut of your mainsail. You can play around with it from there a small amount to fill or flatten the shape from the base point.

Keeping your mast in column while sailing is important and why there are diamonds in the first place. This is especially important when 2-up as a bendy mast will close off your slot and be very slow. Typically I look at the tuning: by adding more spreader rake, you can get more prebend with less diamond tension. Less tension more bend control with rotation, downhaul and sheet, less potential power. By increasing the width you get more latteral support I.e. the mast stays in column better.


I do agree and have been experimenting on spreader width. We started out following the 4.9 max allowable class rules, but are finding some amount wider is faster.

I do not know about the 4.9 or others, but on the Blade anyway, I seem to have been much faster sailing with more mast rake. I am currently running at a point where we are very close to block-block on the main sheet going to weather. When I have tried to move forward on my rake I found the boat did not accelerate nearly as fast up wind in the puffs or react nearly as smoothly when trying to power up for speed.

Keep in mind these are my observations and the pros may have a very differnt appraoch, so try and find what seems to work for you.

Matt