I am wondering what the safe
wind speeds are to use our cruising
spinnaker (I don't know what the exact size is, it was on the
boat when we bought it). Our
boat doesn't have a backstay so on a downwind run I would guess you can get some fairly high loads in the main stays which are swept slightly aft of the
mast.
There is a note in the manual warning not to use the
Jib alone in more than 30 knots of
wind - I suspect this is the reason why.