Anyone got an opinion?

[Bouba]

An unusual engineering feature on the Riviera Belize 66 Sedan is the offset of the twin 1000-hp Volvo Penta IPS1350s that is made possible by the use of jackshafts. This gives more space to the master bath which has stylish his and her wash basins and a large shower stall. A 29 kW Cummins Onan generator is placed between the engines and flanked by battery boxes. The vessel has three en suite staterooms. There are four entry points to the engine room, a plus for the owner/operator, with the easiest access via a walk-in door from the master head. This yacht has remarkably fine interior detailing and amenities.

The above is from BoatTEST.com and they are rightly praising a fine and expensive boat. But it feels to me like it’s going against nature. What do you think?

 

[petem]

Why's it going against nature? The legs / props are in the same please left and right. Wouldn't bother me at all.

 

[Seastoke]

Well it is not simple as shafts so when older more dosh

 

[julians]

I wonder why they didn't push both engines back and have even more internal space. I can't imagine there's anything between the port engine and the ips drive preventing the engine from being as far aft as the other engine because the jack shaft is running through that space.

 

[Beamishken]

Fairly common to install staggered engines in higher performance boats with multiple engine to get them to fit I see no problem with this set up to provide more room might make engine access easier too

 

[Portofino]

2nd word in Rivieras blurb “lifestyle “ followed by “design “ sums up the no doubt huge seakeeping compromise of a 66 IPS twin .
They have swapped fwd internal vol in the std ER for repositioning the tanks .Robbing Peter to pay Paul interns of space utilisation ?

“ lifestyle design” Influenced boaters will like it tied up at the dock most of the time

Re jackshafts
Nothing fundamentally wrong or with stagger .Stagger for narrow beamed hulls to fit huge V8 ,s not really appropriate here as it’s plenty beamy ,
Indeed as IPS goes longer the inclination to jackshaft ie push Kg,s fwd increases to get anywhere near a decent balance .
Watch this space regarding future big IPS instals .Arguably the jackshaft port engine is the better place .

As said they have destroyed storage / wardrobe space with Fwds tank position coincided with trying to balance the hull up a kinda 1/2 hearted nod to seakeeping.But i am not fooled .

Wouldn’t even bother stepping aboard at a show

Yuk .......that’s my 3 letter opinion

 

[rubberduck]

So long as its balanced should be OK, boat not for me however.

 

[Deleted User YDKXO]

As said they have destroyed storage / wardrobe space with Fwds tank position coincided with trying to balance the hull up a kinda 1/2 hearted nod to seakeeping.But i am not fooled .
)

Thats the only thing about the layout that makes any sense because the tanks will be at or close to the CoG and therefore changing fuel load will not alter the trim of the boat. Of course how you get at the tanks for inspection or cleaning is another matter. As for the staggered engine layout, at least it gives better access to the inboard side of each engine for maintenance but of course thats not the reason the layout is as it is. One thing is for sure though and that is that Riviera is an experienced boat builder so this design would not have been adopted without a great deal of thought

 

[MapisM]

Fairly common to install staggered engines in higher performance boats with multiple engine to get them to fit

Not that this affects one bit the matter which is being discussed, but that's a very common misconception.
Even Bulleri gave the same explanation in the video where he tested the Cigarette Marauder, urgh!

Fully staggered engines (which the above are NOT, btw: they are semi-staggered) became a de facto standard in high performance monohull because they allow a lower and closer placement of the propellers, which ultimately means higher performances.
Non-staggered big block V8s have been around for decades, also in racing boats, so they can indeed be squeezed also in very narrow monohulls.
Better access is also a bonus of staggered engines of course, but that's just a side show.
The rationale behind them was and still is strictly performance-related.

 

[MapisM]

On second thought, what I just said in the previous post reminded me of one thing that I don't like/understand, in reply to Bouba's question.
More than the semi-staggered layout (which I'm unable to judge because there must be more than meets the eye, behind that choice), it's the engines placement pretty far from the keel that looks weird.
Placing the genset in between looks like a sort of afterthought, in this respect.
Btw, they could have at least exploited one of the possibilities offered by IPS propulsion, i.e. the engines placement not longitudinally aligned.
By putting them in a sort of V towards the stern, they could have placed the pods lower and closer together, which afaik is always a good idea.
But this is just armchair naval architecture, obviously...