[Vitesse473]

If you fly a symmetric off the bow you will end up with nothing particularly good going on, the sail will be twisted and mis-shapen with no shoulders. The sail is not likely to draw, and if you can get flow over it, it may not do much more than pull laterally. Asymms and symmetrics have very different profiles and shapes.

If you want give to, it a try in light air, but I don't think the end result will be very serviceable.

I second that! Square peg in round hole comes to mind. Having raced J105's, J90's, Nelson Marek's and a few other asymm friendly boats, you just can't make a symm spinnaker work properly without the pole. Just do a little research on the dynamics of each.

I actually re-rigged my Beneteau 473 for a symmetrical spinnaker because I knew it would vastly improve the performance of this Groupe Finot (read, Vendee Globe lineage) designed boat when sailing anywhere from a beam reach to running. Although I have both kite types on board, we flew the symm the entire 750 miles from San Diego to Cabo almost entirely on rhumb line. There were quite a few faster boats that fly asymms that came in after us. We had both weapons on board and chose wisely!

So, no, don't bother. It'll be a mess. You might look for a local J24 or J105 fleet and see if you can get on board. Race some beer can regattas to get a feel for how things work. That's the best way to fully understand the dynamics of the asymm kite.

Lastly, if you choose to fly a symm kite, just get a pole that is equal to your "J" measurement (horizontal length from mast to headstay). Once you have everything rigged properly, go out and enjoy sailing at its best (read, asymms are too easy ;-)

 

[Vitesse473]

IMHO, I think it is not sound advice to suggest you can fly a symmetrical spinnaker off the bow. It just doesn't make sense to take one of the clews on a symm kite to the bow (thus making it a tack). That would put the other clew way to high off the water, which causes two issues. For one, the spinnaker sheet wouldn't clear the boom unless you ran a stout twinger amidships. For two, you'd never be able to properly trim the sail no matter if you were on a close or broad reach. Running, forget about it!

I've attached a shot of us flying my symmetrical spinnaker, and a photo of another boat flying an assym (the pink kite). Just take a look at how that symm kite is built and try to imagine attaching one of the clews to the bow. Can you see what would happen to that shoulder on the upper right portion of the sail? How about the left side? What about the foot? Notice the difference in cut between the two photos. Would be UGLY!! This hopefully gives a clear picture of how these two sail types are cut differently.