Stability

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Reight
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Stability

Post by Reight »

2023 R8 OB. Why does our R8 rock back and forth so easily at anchor when people move about? Or tilt so much when underway if not almost perfectly load balanced? Why does the boat list to the left at dock? See pic. Three batteries at aft port side? Just curious.
sailor55330
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Re: Stability

Post by sailor55330 »

Cobalt redesigned the even numbered R series with less deadrise, meaning a less deep vee presumably more better wake/wave production. The cost comes at a flatter hull that will roll more at anchor

Listing could be batteries or any source of weight—fuel, ballast, etc. it doesn’t take a lot
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stifflkd
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Re: Stability

Post by stifflkd »

Less deadrise will rock less not more. Is it single or dual OB's. A lot of weight higher up adds a higher righting moment. It would be interesting to hear from R8 sterndrive owners. With the weight lower in the bilge and within the footprint of the hull I would think this issue is not felt.
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billk2632
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Re: Stability

Post by billk2632 »

Less deadrise, no IO engine sitting low and a tower are going to add to the roll factor - keeping full(er) water and fuel tanks will help. As far as while underway, the deadrise doesn't not have as much impact there, deadrise is going to allow the boat to ride better in rough water. When you get into a 25+ boat, you need trim tabs - they can make a world of difference in weight distribution, planing with a load etc. I would seriously consider trim tabs - mine does not have them, but I see many R's with them.
3 batteries, plus all the port side storage does not help. I would consider moving two of the batteries to STB if you can - my R5 has two batteries - 1 Port 1 STB.
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Reight
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Re: Stability

Post by Reight »

Its a twin OB and we have trim tabs. All makes sense, thanks for the opinions and responses. Poor design having 3 batteries on one side. Probably cheaper that way. Looking at moving one of the batteries to SB side. Or just storing a 50lb bag of sand there ;-)
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bruceb58
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Re: Stability

Post by bruceb58 »

stifflkd wrote: Sun Oct 29, 2023 11:23 am Less deadrise will rock less not more.
Exactly!
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