>>8:1 is too much. You'll rip the tack out of the sail unless it's reinforced.

In my experience the tack on the 17 sail needs to be reinforced anyway. The grommets on the last two sails I got (2005 & 2007) were total junk. They immediately started pulling out of the sail. I took the sails to my local shop and had them add a strap of nylon webbing through the grommet and up about 6" to help better distribute the downhaul load to the tack. I don't know why Hobie uses these lousy groummets on the 17 sail. I'm pretty sure they use better ones on the 16 and 18 sails. In any case, it's a relatively easy fix and now I can bottom out my downhaul.

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