PVC bunks and scuppers

Hello, new Tandem Island owner here. I've spent a lot of time reading through the forums about the Hobie cradles vs PVC bunks. Since trailers are hard to come by these days, I am stuck with cartopping for now, and I figure the PVC will be easier than the cradles for that application. (I already cartopped once on foam blocks and dented the hull, doh!)

After all that reading I am still confused regarding the "scuppers"...

Hobie reps keep saying PVC bunks can push the scuppers up through the boat, are they talking about those little black protusions for the venturi drains under the seats? https://www.kayakfishing.blog/uploads/2 ... n_orig.jpg Can these just be removed and would that leave a hole in the hull to be patched?

Or are they talking about the two center holes for the cart that are reinforced with black plastic pipe, do these also need special care on the PVC?

Thanks for your help!

The seat drains can be removed or you can cut a notch in the pvc where they rest. The hull deformation concern is from the cart scuppers. The scuppers can rest on the pvc and carry the load, forcing the hull to deform upward where the scuppers are. This could lead to cracking and definitely increases stress on the hull. This is aggravated if you use ratchet tie-downs or otherwise secure the kayak too tightly against the bunks.

I have an Oasis, not an Island. I experimented with different PVC diameters and observed that 1 1/2” PVC did make contact with and pressure the scuppers upward while 2” did not. I used gray 2” schedule 80 PVC conduit for my bunks. After 5 years and many thousands of miles of trailering I have had no issues. I did remove the seat drains.

Matt will likely respond to this post and advise you strongly to not use PVC bunks and instead use the Hobie recommended cradles, as he should. And do note that the manufacturing process is such that no two kayaks of the same model are exactly the same. What works for one may not work for another.

Peter

Thanks for the info, I was going to get 2" but sounds like 3" pvc is preferable.

I would like to get a trailer with the cradles eventually, but not sure how to make the cradles work on top of my SUV racks. I'm trying to find a used trailer but for now I have a very expensive plastic brick taking up my garage that I would love to get on the water before summer is over.

One option… Some roof-toppers have attached the PVC tubes or cradles to ladders that are then secured to their roof racks. Search these forums for the word “ladder” and you should find several posts with photos. As with trailer mounting, you must permit the PVC tubes to flex some to better match the hull shape.

Of course, the amas add another complexity to PVC bunks, especially mounted on top of a vehicle. And whether craddles or bunks, added weight will affect handling and could exceed vehicle or roof rack limits. There is a thread here somewhere on roof-topping Islands. I roof-topped a pair of Outfitters for a few years and am very happy to be using a trailer for the Oasis.

Peter

I am a big fan of the ladder/PVC pipe system, but the added weight could be a problem on your vehicle. The positive factors of the ladder use are that it will then transfer to a trailer and quickly mount, it gives excellent support to the boat and in some situations it can be slid or pivot to facilitate unloading.
It is my belief that a boat experiences more stress during transport than use on the water. So I have tended to make my carrying systems as stiff as possible.

Thanks for the replies. I found a decent deal on a used wave ski trailer 16'. The bunks weren't really supporting the hull very well so I grabbed my old inflatable SUP, blew it up half way, and put that under kayak. It seems to be working well so far as a temporary solution, it supports tons of surface area on a one inch cushion of air, and it still straps down okay. Hobie should look into making inflatable bunks, it could be an especially good solution for cartopping or long term storage I think, and shouldn't cost much more than the cradles.