My 5.3 black tip is my only sail to run on a 400cm mast and it annoys me pacl two masts i small car, how bad would it be to rig it on 370cm with a long extension ? I am 74kg
I hope this is in right section
Select to expand quoteonshoreroy said..
My 5.3 black tip is my only sail to run on a 400cm mast and it annoys me pacl two masts i small car, how bad would it be to rig it on 370cm with a long extension ? I am 74kg
I hope this is in right section
The only real way to know is to try it. 
Generally speaking, the sail will probably rig flatter and feel a lot more flexy/springy, but it depends a lot on the way the sail is shaped. For your weight it is more possible that it will work just fine, but it's a 'suck it and see' thing.
In a pinch sure... In a surf zone you'd face the problem of weakened mast extension.
Also a 5.3 is a lighter wind sail so using a 400 is ok but 370 will definitely be too soft. May be ok for steady winds.
In stronger winds it'll flex and depower and may cause the center of effort to move. It'll take longer for the sail to respond.
What's your luff length?
Select to expand quoteManuel7 said..
In a pinch sure... In a surf zone you'd face the problem of weakened mast extension.
Also a 5.3 is a lighter wind sail so using a 400 is ok but 370 will definitely be too soft. May be ok for steady winds.
In stronger winds it'll flex and depower and may cause the center of effort to move. It'll take longer for the sail to respond.
What's your luff length?
418 for 5.3 and 403 for 5.0
Roy, I reckon try it. I run shorter masts in some of my sails + extender. However, I do it for tuning, not for convenience. I'm the same weight as you.
Select to expand quoteonshoreroy said..
My 5.3 black tip is my only sail to run on a 400cm mast and it annoys me pacl two masts i small car, how bad would it be to rig it on 370cm with a long extension ? I am 74kg
I hope this is in right section
As somebody else has said you have to try. I used a 370 on a Hot Sails Maui KS3 4.9 that has a 407 luff and it was way too soft. I regularly use a 430 mast on my Point-7 ACX 7.5 with a 476 luff and it works great.
The HSM QU4D 5.2 is advertised as rigging on either but at 90kg I did not like it on the 370.
5.0 will be fine and depending on board used (volume, width, fin, shape) 5.3 may not bring much more as it'll add weight to the board.
Black tip is flex top, which mast?
I always run my Naish boxer 6.2 with 42-44cm extension on 400 mast, and Chopper S and M often on 310cm mast with 35-42cm extension and they work absolutely fine. Chopper S and M on 310 feel super soft but if you consider the wind needed for Chopper S, an umbrella will pull you on to the plain. Softness helps a lot in gusts in these winds. Can Boxer be more efficient on 430cm, maybe, but fortunately/unfortunately windsurfing is very dynamic sport with wind speeds and water conditions fluctuating in real time.
Speed sailors often mix and match tops and bottom mast halves to gain stiffness maybe a bigger bottom half and the long extension? Bit of a suck it and see!
