Best Setup for a backstay tension adjuster


Never having seen my J24 ‘project’ boat with the mast up, I am a bit confused trying to rig the backstay tension adjuster.
I have the lines leading back to either side of the cockpit just forward of the traveler. But I am sure that I need to insert a Vang-type pulley system to gain some mechanical advantage in tightening the backstay.
Can anyone share a photo (or refer me) of a good way to rig this on my boat? I have an empty eye strap on the starboard rear corner of the cockpit seat, which I presume had a vang-type setup attached - but i have never seen this boat rigged, so I am seeking some good advice.
Thank you!
If I understand your description correctly, the "empty eye strap on the starboard rear corner" is for the spinnaker sheets.

Here is a picture of the setup from my boat. If you zoom in, you can see the detail that I describe below.
You should have a pulley system that each end of your backstay goes through and then clips into chainplates on either end of the transom. The other end of the pulley system should clip into something mounted on the transom too. On my boat, each end of the the line that feeds through the pulley system goes through an eye pad on either side of the rear cockpit lower corners. It then leads forward, just past the traveler to a block, and then turns up to the top of the cockpit where a person can adjust the tension, and lock it in with some clam cleats.
Hey, Durbano -
Thank you so much for this picture!
I have the same eye straps (smaller than pad eyes) on my boat, and it looks like I can copy your rig configuration.
I am having a bit of trouble enlarging your photo - probably because I am not on Instagram. Is there a regular "pic" version of this photo that you could send me? That would be great!
Many thanks!
No worries! In the process of finding the original, I found a better picture that has everything I described. Attached below.


Backstay and pulley system setup J24.jpg
Wow! Perfect image - and it explains everything.
You maintain the equivalent capability to adjust the backstay from either side of the cockpit, with a greater 'purchase' and power from the 3:1 efficiency gain from the upper and lower blocks!
Thank you so very much! You are THE BEST!
From my experience, the additional purchase provided by the block on the stern rail isn't necessary. It's most common to run the line through the fairlead at the aft end of the cockpit, up through the block dangling below the split, and back down to the other fairlead...then to wherever you want to go.

I never sensed that I needed more purchase.

Thank you, Vince. I wondered about the necessity of the additional purchase for a J24. I had a pretty hefty system for backstay tension on my J30 - but it was a heavier rig and required a greater force to bend the mast. Nothing in the pulley system led forward - everything was a maybe 5:1 purchase in the adjuster attached to the transom. Different forces, different requirements.
Many thanks!
Vince - I generally agree with you on the purchase being a bit of overkill here. However it's how my boat came when I bought my boat in Seattle, and it's how it got rigged here in Berkeley by the guys who maintain our local fleet. It's also nice that my tween daughter can make the adjustment without complaint when the heavier me is sitting on the rail. ;)

I think it's a minor thing, according to preference. I was just suggesting that it might not be necessary if one were rigging it for the first time. It can be a good thing though to be able to get it approximately where you want it with one yank at the leeward mark, when racing.

Mine was rigged as in the photo attached, with the lines going forward through small blocks hanging on straps below the traveler, then crossing and going to a cam cleat on each side. They're right there for the skipper to give it a yank. I think that setup was from Harken.



  • Backstay Adj Lines.jpg
    Backstay Adj Lines.jpg
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